ASTB Mechanical Comprehension Test

Total Flash Cards » 229
Text Size: S | M | L

The wheels are connected by a belt. As the wheel on the left makes one revolution, the wheel on the right makes


less than one revolution
exactly one revolution
more than one revolution
more than one revolution

If the wheel on the left turns clockwise, in which direction does the wheel on the right turn?


Clockwise
Counterclockwise
Counterclockwise

A woman sits in a dragster at the beginning of a race. As the light turns green, she steps on the accelerator. At the moment the dragster begins to accelerate what is her weight pushing into the seat relative to while the car was stationary?


Less than stationary
The same as stationary

More than while stationary
More than while stationary

All the gears in the system are moving and Gear 1 rotates clockwise. What other gears in the system also rotate clockwise?


2 and 4

2 and 5

3 and 5
3 and 5

In which case is less force needed to move weight (W) up the ramp?


A

B

The force is the same in each case.
A

If each pendulum is released from the position shown, which pendulum requires the longest amount of time to complete one swing?


A

B

The times are equal
B

The voltage drop or potential difference is greater across which resistor?


Ra

Rb

It is the same across either resistor
It is the same across either resistor

If the large portion has 3 times the surface area of the small piston, how far must the small piston be pushed down to raise the large piston 1 inch?


1/2 inch

1 inch

3 inches
3 inches

If you had to swim across a fast moving stream exactly perpendicular to the banks, when you arrived at the far bank where would ur position be relative to where u started across?


Upstream from where you started

Directly across from where you started

Downstream from where you started

Directly across from where you started


According to the answer sheet given, directly across from where you started, current was not considered in the answer.



Check this discussion: http://www.airwarriors.com/forum/showthread.php?t=4913

If the three squad leaders are to stay on line, which of them must turn the most slowly?


A
B
C
C

In order to balance the scale above, the fulcrum should be moved


toward A

toward B

in either directions
toward B

If the scale was balanced before u moved the fulcrum, which of the balls is more dense?


Ball A

Ball B

They have the same density
Ball B

Where would it be best to hold a pruners' handles while trying to cut a branch?


A

B

It does not matter
B

If the current leaves the battery in the direction shown in the diagram, what is the direction of the current in resistor X?


A

B

There is no current in the resistor
A

The voltage drop is greater across which resistor


Rx

Ry

It is the same across either resistor
Rx

Where is the current greater in the circuit?


Greater at A than B
Greater at B than A
The same at A and B
The same at A and B

X, which has a negative charge, is positioned between a positive charge (A) and a negative charge (B). In which direction will X move?


A

B

Remain where it is
A

In a stream, water flows through narrow and wide sections. In which sections does the water flow fastest?


Narrow section

Wide section

The same through either section
Narrow section

At what point is the velocity of a bullet fastest?


When it leaves the muzzle

When it reaches the top of its arc

When it hits the target
When it leaves the muzzle

The rate of heat exchange is faster between


an ice cube and 100° glass of water

an ice cube and 40° glass of water

none of the above
an ice cube and 100° glass of water

If two glasses of water 40° and glass A was 1/2 full whle glass B was 3/4 full, which glass would melt the more ice in a given amount of time


A

B

They would melt an equal amount of ice
B

Did you read a mechanical comprehension hand out?


No, but I will now.

No! What hand out?

Yes, and I understood everything.
Yes, and I understood everything.

If the large pistion has 2 times the surface area of the small piston, how far must the large piston be pushed down to raise the small piston 1 inch?


1 inch

2 inches

1/2 inch
1/2 inch

When the wheels X are turned at the same speed, which turns wheels Y faster?


Wheel X1

Wheel X2

They turn wheels Y at the same speed
Wheel X1

Imagine if wheels X where the front sprocket of a bicycle and wheels Y the rear sprocket. Which system would be hardest to pedal up a hill?


System A

System B

They would have the same difficulty
System A

If wheel X1 is exactly twice the size wheel Y1, and wheel X1 is turned one time, how many times will wheel Y turn?


One turn

Two turns

One half turn
Two turns

In system A, as wheel X1 makes one revolution, point A


travels a greater distance than point B

travels a smaller distance than point B

travels the same distance as point B
travels the same distance as point B

Above is a cross section of a wing. Air travels over it and under it. As the wing moves through the air speed relative to the foil is


greater above the wing

below the wing

the same above and below the wing
greater above the wing

When the plug in the tube is removed, water flows


into the tube

out of the tube

neither way
into the tube

For which position of the weight is the tension on the string at point X greater?


A
B
It is the same for each position
B

When is it more difficult to hold an inflated beach ball under water?


Close to the surface

Down deep

The difficulty is the same at either depth
Down deep

When does a beach ball seem more buoyant?


Close to the surface

Down deep

The buoyancy is the same at either depth
Down deep

Which weight exerts less pull on the horizontal bar from which the weights hang by strings?


A

B

Each weight exerts the same pull on the bar
A

A submarine is traveling through the ocean when its outer hull cracks and air pushes out of its lower right side. In which direction must the rudder be turned to ensure the submarine remains on its heading?


A

B
A

A submarine is traveling through the ocean when its outer hulls cracks and air pushes out its lower right side. In which direction must the submarine be turned to ensure the submarine remains on its heading


towards the port

towards the starboard
towards the starboard

If the board to the left was placed in water, in what orientation would it float?


A higher than B
B higher than A
Perfectly level
B higher than A

If two resistors and a battery are arranged in each of the above circuits, which circuit arrangement has greater resistance?


Circuit A

Circuit B

They have the same resistance
Circuit A

The lever above is anchored just to the left of point A. If one were to raise it one inch measured from point A to the ground, point B would rise


less than one inch

one inch

more than one inch
more than one inch

In which case is more force needed to raise the weight?


A

B

The force is the same in each case
A

Which system requires more rope to be pulled to lift the weight the same distance?


A

B

They require the same amount of rope
B

Which pendulum takes less time to make one swing?


A

B

Each takes the same time to make one swing
A

If pendulum A was the same length as pendulum B, which pendulum would take more time to make one swing?


A

B

Each would take the same time to make one swing
Each would take the same time to make one swing

Newton's First Law
An object in motion will stay in motion, object at rest will stay



in motion

at rest

equilibrium
at rest

Newton's Second Law

Force = Mass *



Gravity

Acceleration

Velocity

Speed
Acceleration

Newton's Third Law

For every action there is



a) an equal and opposite reaction

b) a varied response

c) multiple reactions
a) an equal and opposite reaction

Speed of conduction, which occurs in solids and stationary liquids



a) creates more heat across multiple objects

b) moves the lower temperature from one solid to the other

c) depends on the temperature difference
c) depends on the temperature difference

Butcher Knives, Axes, Nail Cutters, are examples of



Levers

Pulleys

Wedges

Screws
Wedges

This device is typically used to measure wires, spheres, shafts and blocks.



Micrometer

Multimeter

Tape Measure
Micrometer

Compressing air in a closed place will _______ the volume and ______ the pressure



decrease, decrease

decrease, increase

increase, raise

increase, increase
decrease, increase

Bernoulli's principal



applies to liquids

applies to air

involves flow and pressure

all of the above

all of the above

This class of lever is like your everyday crowbar. The fulcrum is in the middle with the resistance force, the load, on one end and the effort force on the other. An example of this would be a seesaw.



First class lever

Second class lever

Third class lever
First class lever

On this class lever, the fulcrum is on the end, the resistance force, the load, is in the middle,and the effort is at the other end. An example of this would be a wheelbarrow.


First class lever

Second class lever

Third class lever
Second class lever

On this class lever, the fulcrum is on the end of one side, the effort force is in the middle, and the resistance force, the load, is at the the top. An example of this would be a baseball bat.


First class lever

Second class lever

Thrid class lever
Third class lever

The formula for force is
mass times acceleration

The maximum weight, W, that can be lifted as shown with a pull of 100 lbs is


100 lbs

200 lbs

300 lbs
200 lbs

A 5 kg wad of clay is tied to the end of a string. A 300 gm copper moving horizontally is embedded into the clay and causes the clay and ball to rise to a height of 0.2 m. The intial velocity v¹ of the ball is nearly


6.3 m/s

7.3 m/s

8.3 m/s
8.3 m/s

Which exerts a larger force over a distance?


A small force over a long distance

A large force over a short distance
A small force over a long distance

The formula for Work is
Force x distance
The formula for Efficiency is Workout/Workin , since friction causes inefficiency. The fraction is never greater than 1.
A force acting on a surface is called pressure, and is calculated by
Pressure = Force / Area


Can be used for fluid pressure and atmospheric pressure

An observer standing on the ground sees you running 55 mph. If you were running towards the caboose, what would the velocity be?


45 mph

50 mph

52 mph

55 mph
45 mph
A 300 lb weight rests on a hydraulic surface with an area of 376 square inches (2 square ft). What force is needed to act upon the smaller surface having an area of 36 square inches (six by six)? 28.8 lbs

Pressure in liquids that are not moving is called ________ pressure, and is caused by ______. If fact, as you go twice as deep, the pressure will be ______ as much.


hydrostatic/gravity/increases

hydraulic/force/increases

hydraulic/gravity/decreases

hyydrostatic/force/decreases
hydrostatic/gravity/increases

____________ pressure is caused by the weight of the air between the earth's surface and space.


Hydraulic

Atmospheric

Hydrostatic

Atmospheric
Energy travels from objects of different temperature in the form of _____ through the process of conduction and convection and radiation. Heat

_________ occurs in liquid and gases by calculating currents caused by a difference in density. All objects radiate heat; most of which is infared radiation that is not visible. ________ heat transfer depends on the temperature difference. The _________ are not important. Nor does it matter whether one is cold rather than hot. The heat will flow from the hot object to the cold object. The rate of heat transfer will be greater for a larger temperature difference.


Convection/Radiation/Mass

Radiation/Conduction/Temperature

Conduction/Convection/Temperature

Convection/Conduction/Temperature

Radiation/Convection/Weight

Conduction/Radiation/Temperature
Conduction/Convection/Temperature

Electrical forces are caused by electrical charges which may be positive or negative.

Which of the following is true?



Opposite charges repel, like charges attract.

Electrical forces decrease as the distance between charge particles increases.

Particles that are apart will exert greater forces on each other than particles that are close


Electrical forces decrease as the distance between charge particles increases.

This circuit element dissipates energy through heat


Resistors

Capacitors

Inductors

Diodes

Transformers
Resistors

This circuit element stores electrical energy between two parallel plates


Resistors

Capacitors

Inductors

Diodes

Transformers
Capacitors

This circuit element stores magnetic energy


Resistors

Capacitors

Inductors

Diodes

Transformers
Inductors

This circuit element restricts current to only one direction. A semiconductor used as a rectifier. Rectifiers convert AC to DC



Resistors

Capacitors

Inductors

Diodes

Transformers
Diodes

This circuit element is used to convert electricity from one voltage to another


Resistors

Capacitors

Inductors

Diodes

Transformers
Transformers
The two kinds of circuits that you are responsible for are:
Parallel circuits
Series circuits
These kinds of circuits are identifies by seeing sever circuit elements, (resistors, lights, etc.) running between parallel to each other between the positive and negative sides of the power source Parallel circuits, and in this circuit, the current gets divided between two or more elements
In these kinds of circuits, all of the circuit-elements are in a row along a single wire similar to a set of Christmas lights Series circuits, and in this circuit, the voltage will continue to drop as it passes through elements until it has finally dropped to 0.
What is Ohm's law?
I = V/R
As you follow the path of the current from the positive node away from the battery and through an element, the voltage will be the same as the bettery until the current goes through the element. After crossing a resistor there will be a _________ Voltage drop

The theory behind leverage is that the longer the lever, the more ______ u produce.


force

torque

distance

weight

torque, which is the product of force and distance

Doubling the length of the lever-arm would ________ the torque that you apply.


double

The torque created by the hand must _______ the torque produced by the weight before it can be lifted.



Equal

Double
Equal

Left Side:
Force = 60 lbs
Distance to fulcrm = 8 ft



Right Side:

Force = ?

Distance = 15 ft



Force on the right side equals



30 lbs

32 lbs

34 lbs

36 lbs
32 lbs

The _______________ of a lever is calculated by dividing the arm-length that you are applying a force by the arm-length of the resisting weight.


Torque

Effort

Force

Mechanical Advantage

Mechanical Advantage

What is the formula for the Mechanical Advantage of a lever?
Effort Arm / Resisting Arm


MA = length of effort arm ÷ length of resistance arm.

What is the Mechanical Advantage of in the diagram?


1

1.44

1.88

2
1.88

You may see problems where weights and forces are acting on a single lever arm. It's possible that you'll see a combination of both. In these cases, you have to realize that torque acts in two directions. What are the two directions?


They repel

They attract

clockwise and counterclockwise


clockwise and counterclockwise

Solve for the unknown force or distance


11 lbs

15 lbs

10.9 lbs

33 lbs
11 lbs

A pendulums has three weights attached, each 8 in away from each other. One string is 7 in long and has a 3 lb weight. The other two strings are 5 in long. Each have a weight of 4 lbs and 8 lbs. All of them are swung from the left to the right.


Which of the ff is true?



a) The one with the longer string takes the longest to make one complete swing

b) With the two 5 inch strings, the string with the 8 lb weight will take longer to complete a swing

c) All of the above

a) The one with the longer string takes the longest to make one complete swing

The weight does not matter with swing time.

You had two tennis balls and held them over a 10 story building, and you dropped Tennis ball A straight down while Tennis ball B was tossed horizontally first, but released them at the same time. Which would hit the ground first?


A

B

They hit the ground at the same time
They hit the ground at the same time

Pushing a weight up an incline requires only a fraction of the force needed to lift the weight directly. This fraction can be found by calculating



a) the ratio of the slope-length divided by the height

b) the opposite leg divided by the hypotenuse of a right triangle (sin 0)

c) all of the above
all of the above

For a height of 5, and a slope-length of 10, the Mechanical Advantage in the diagram is


10

15

1

2

2

The mechanical advantage for a pulley system



a) equals the number of ropes within the system

b) equals the number of pulleys within a system

c) equals the maximum weight of the object

e) equals the maximum effort exerted

equals the number of ropes within the system



Only MOVEABLE pulleys provide mechanical advantage

The load is supported by how many strands of rope?



1

2

3

4

3

If the pull of the truck in the diagram is 100 lbs, what is the maximum weight of the object?


100 lbs

200 lbs

300 lbs

400 lbs

400 lbs


NOTE: Also the weight will raise 1 ft for every 4 ft you pull

When several ropes are in contact with the weight, they all contribute equally. Tension is defined as


the force that the rope sustains internally

the force that is needed to move the weight

the force that the rope sustains internally



the force that is needed to move the weight is equal in the rope where someone is pulling it.

In the figure, there are ropes holding the weight up. Therefore they each contribute ____ of the force needed to hold the weight.



1

1/2

1/3

1/4
1/3

This specifies the change in position of a point in reference to a previous position. In simple terms, it's the difference between the initial position and the final position of an object.


Displacement

Movement

Range

Volume
Displacement

R = (D*R)/d is the formula for


Radius

Range

Gear Revolutions

Gear Revolutions


r=(D*R)/d ; r*d=R*D

Hydrometers use floats to measure


specfic gravity

displacement

hardness of water

amounts of water
specfic gravity

Specific gravity is the weight of a ______ compared with the weight of the water.


solid

gas

liquid

mass
Liquid

The liquid with the highest specific gravity will cause


the float to rise higher in the glass tube

the weight to sink to the bottom of the glass tube

the float to maintain a balance in the center of the glass tube
the float to rise higher in the glass tube

Pliers and scissors are ________ levers and explain where the fulcrum of the lever is.


First Class

Second Class

Third Class

First class.


The fulcrm is in the middle

A nutcracker or wheelbarrow are _________ levers.


First Class

Second Class

Third Class

Second class.



The fulcrum is at one end, load is in between.

Tongs or tweezers are examples of _________ levers


First Class

Second Class

Third Class

Third Class


Fulcrum is at one end, effort is in between.

In pulley's, the smaller pulley will turn _______ than those larger than it.


Faster

Slower

Same Speed

Faster


It has to "keep up" and therefore turns faster.

a* d = A * D


a = area

d = displacement

A = bigger area

d = bigger displacement



This is the formula for what?
Mechanical Advantage in a piston

An axe is classified as a wedge, which is an


inclined plane

first class lever

second class lever

third class lever
inclined plane

The __________ the fulcrum is from the resistance arm, the __________ amount of force that is required to lift the weight and the _______ the resistance arm will travel.


closer, greater, higher

farther, less, higher

closer, greater, lower

farther, greater, lower
closer, greater, higher

No electricity flows through burnt out bulbs, but a ________ can bypass it if connected on both sides. It tells you the total voltage in a circuit.
voltimeter

Which of the following is true:


Current and Voltage varies in a parallel

Current is constant in a series, voltage is not

Voltage is constant in a series, current is not

Current and Voltage are constant in a series

Current is constant in a series, voltage is not


Current * resistance = voltage
The current with the _______ resistance is usually in series, because it forces the current through all resistors. greater

In a 2 pulley system, the movable pulley will only move up half the distance, and spin half as much as the fixed pulley.
No answer. That was a statement.

What is the rpm for this wheel, that requires 2 contacts per second?


15

16

48

8

15


twice per second = 120 contacts per minute. 8 rods on wheel. 120/8=15

Heat is a form of


calories

motion

energy

pressurization
energy

On a standard day, at sea level, assuming static conditions, the speed of sound is


1100 ft per sec

1200 ft per sec

1300 ft per sec

1425 ft per sec
1100 ft per sec

For a plane to fly, air flowing over the top of a wing creates a vaccum, while the air flowing over the bottom


a) remains at approximately the same air pressure

b) decreases in air pressure, allowing the wings to glide

c) increases in pressure, pushing the wings upward
a) remains at approximately the same air pressure

The diagram depicts airflow around the wing of an aircraft. Most of the lift is caused by


a) increased air pressure on the bottom side (side B)

b) increased air pressure on the top side (side A)

c) decreased air pressure on the bottom side (side B)

d) decreased air pressure on the top side (side A)
d) decreased air pressure on the top side (side A)

In the diagram, which of the ff statements is not true?


a) pulley 2 would spin faster than pulley 4

b) pulley 4 would spin faster than pulley 3

c) pulley 1 would spin faster than pulley 3

d) pulley 4 would spin faster than pulley 5

c) pulley 1 would spin faster than pulley 3


according to the book

Which tool below is the best for cutting metal?


hacksaw

chainsaw

rotary saw

handsaw

hacksaw


hacksaw was designed for metal.

Which of the ff is a type of lever?


elevator

seesaw

door hinge

electrical cord
seesaw

What is the formula of force for a lever?

Fᴱ = FL dL / dᴱ



Formula can be changed to

Fᴱ dᴱ = FL dL



Fᴱ = effort force (N, lb)
FL = load force (N, lb) (note that weight is a force)
dL = distance from load force to fulcrum (m, ft)
dᴱ = distance from effort force to fulcrum (m, ft)

Approx how much force must be exerted to lift the box?



67 lbs

100 lbs

250 lbs

258 lbs

67 lbs


Fᴱ dᴱ = FL dL

Fᴱ 30ft = 200lb * 10ft

Fᴱ 30ft = 2000lbft

Fᴱ = 2000lbft/30ft

Fᴱ = 66.6666666 or 67 lb

Which wrench would require more force to turn a bolt?


Wrench A

Wrench B

No Difference

None of the above
Wrench A

In order to move the block five feet, how many feet of rope would have to be pulled?


5

10

15

20
15

The number of cranks the crankshaft of a V-6 engine has is


2

4

6

8

6


6 pistons, 1 crank per piston

Pulley A is the same size of Pulleys B and C, and twice the size of Pulley D. For each revolution made by Pulley C, how many revolutions will Pulley A make?


one

two

three

four

two


according to the book, two.

In order to lift a 100 lb load onto a dock five feet high, using only 25 lbs of force, how long of a ramp would have to be used?


5 ft

10 ft

15 ft

20 ft

20 ft


100 / 25 = 4

4 = required MA for an inclined plane
4 * 5 feet high = 20 ft

One horsepower is equal to


a) 33,000 ft-pound work per min

b) 150 lbs of force in an hour

c) 950 psi

d) 17,500 ergs
a) 33,000 ft-pound work per min

In the diagram, how many pulleys are turning in a clockwise direction?


one

two

three

four

four


according to the book, 4

Wheel A has a diameter of 10 inches. Wheel B has a diameter of 25 inches. If both revolve at the same speed, which wheel will travel the most distance in the same amount of time?


Wheel A

Wheel B

Same distance

Cannot determine
Wheel B

How many gears are turning in a counterclockwise direction?


two

three

four

five
three

If Gear 1 has revolves twice, how times will Gear 2 revolve?


1

2

3

4

1



The picture would have 2 gears, a small 10 tooth, and a large 20 tooth.

In the figure, for each complete revolution of the cam, how many times will the valve open?


1

2

3

4
3

What is the area of a cylinder?

2(π r²) + (2 π r)* h

In the hydraulic system depicted, the cylinder on the left has a diameter of 2 inches and the cylinder on the right has a diameter of 6 inches. If 100 lbs of force was applied to the cylinder on the left, what force would be exerted on the cylinder on the right?


300 lbs

33.3 lbs

900 lbs

450 lbs

900 lbs



In the design, which tank(s) will overfill?


Tank A

Tank B

Tank A and C

Tank B and C
Tank A and C

Which of the following are not parts of a braking system of an automobile?


discs

master cylinder

axel

wheels

axel

On a braking system, the axel supports the wheel, but is not part of the braking system. The _________ provides hydraulic force to press discs (or pads) against wheels of a vehicle, making use of the force of the friction to slow (or stop) the wheels.


discs

pads

calipers

master cylinder
master cylinder

When a machine magnifies force, it is referred to as


magnification factor

mechanical advantage

leverage factor

efficience factor
mechanical advantage

A pitch is


a) the distance between the threads of a screw

b) the gap measurement of a spark plug

c) the angle measurement of a simple lever

d) one of the four basic measurements of force
a) the distance between the threads of a screw

When an object is at equilibrium


a) its velocity does not change

b) the object speeds up

c) the object is at rest

d) the object changes direction
a) its velocity does not change

Equilibrium is


a) when at object is at rest

b) when 2 or more forces act to cancel the effects of each other

d) when the velocity speeds up

b) when 2 or more forces act to cancel the effects of each other


An object at equilibrium may be at rest, but not necessarily so.

An example of a simple machine is



a door hinge

light switch

can opener

all of the above
all of the above

When a helium-filled ballon rises, the force responsible is


friction

air pressure

buoyancy

gravity
air pressure

In physics, power can be defined as


work/time

energy/efficiency

leverage/mass

friction/drag
work/time

The force acting on an object dropped from a building is


buoyancy

elastic recoil

gravity

equilibrium
gravity

If you remove your foot from the gas pedal in ur car, it will slowly coast to a stop. The force which causes this is


friction

gravity

velocity

magnitude
friction

If a driver wheel is present, the adjacent wheels will rotate according to how _________ to the center the driver wheel makes contact with them.



close

far

close


The closer to the center, the faster it will move.

By increasing the length of the lever arm, the effort is increased, enabling a valve to blow off at a higher pressure. So if you...



a) move the lever closer, this will cause the valve to blow up at a lower pressure

b) move the lever farther, this will cause less effort

c) move the weight towards the fulcrum, this will cause an increase on pressure

d) move the effort closer, this will cause the valve to blow up faster

b) moving the lever farther will cause less effort


NOTE: ...and lets the valve blow up at a lower pressure
What is the formula to find the volume of a sphere? 4/3π r³
What is the formula to find the area of a sphere? 4 π r²

If two weights hang from two different strings attached to a bar, less pull is exerted by the weight of less weight.


Which of the ff is true:



a) the weight does not matter

b) the length of the string does not matter

c) the distance the weights have from the ground does not matter
b) the length of the string does not matter

The deeper you go with an inflated ball, the more difficult it is to hold it underwater. So the buoyancy


a) will not change, no matter how deep you go into the water

b) will increase, depending on how deep you go into the water

c) will decrease, depending on how deep you go into the water
b) will increase, depending on how deep you go into the water

Rate of heat exchange is _____ through objects of greater temperature difference


slower

the same speed as

faster
faster

Think about putting your thumb on the end of a hose makes the water spray.


a) water flows faster through narrow areas that it does through wider

b) the same amount of water will flow through the smaller and larger part of the hose at a given time

c) all of the above
c) all of the above

This kind of engine consists of an intake, compression, combustion, and exhaust.


2 stroke

4 stroke

8 stroke
4 stroke

What is the mechanical advantage of a wheel and axle?


radius of axel to handle divided by the radius of the drum


radius(axel to handle)/radius(drum)

Statics and Equilibrium
Formula for a moment?
Force * distance

________ energy is stored in an object while _________ energy is energy in motion.


Kinetic, Potential

Potential, Kinetic

Pressurized, Freeflow
Potential, Kinetic

I = Q/T

Define I, Q, T



Current, charge, time

Voltage, momentum, time

Voltage, charge, time

Current, force, time
Current, charge, time

This device measures the current flow in a circuit


Ammeter

Voltmeter

Multimeter
Ammeter

This device measures does the job of both measuring the flow in a current and the voltage


Ammeter

Voltmeter

Multimeter
Multimeter
The formula for Power is Power = volts * amperes

Units for a charge is


coulomb, C

ampere, A

volts, V

watts, W
coulomb, C

Units for current flow are


coulomb, C

ampere, A

volts, V

watts, W
ampere, A

Vise


MA = (2*pi*length of handle) divided by what?


pitch of thread

Formula of Weight is


Mass * Gravity

Gravity is equal to



9.81 m/s²

32.3 ft/s²

22.1 mph

9.81 m/s²


All the other answers are off by 0.1 only.

32.2 ft/s²

22 mph

The formula for Density is
Mass / Volume
The formula for Relative Density is Density / Density(Reference Material)

If you add salt into a liquid, the solution has a lower freezing point. This is because


a) there is an increase in specific gravity

b) there was a decrease of density in the reference material

c) the volume of the saltwater solution decreased

a) there is an increase in specific gravity


Specific gravity usually means relative density with respect to water. The increase in the density of the liquid compared to regular water or gas makes salwater "more solid."

Heat always



distributes between objects

travels from hot to cold


travels from hot to cold

Compressing air in a closed place will decrease the volume and raise the temperature


a) True

b) False, temperature will stay the same.

c) False, volume will stay the same
True

A square plate is hanging by 4 wires (one on each corner). One breaks, and it's hanging by only 3 wires now.


a) each wire now carry the same amount of weight
b) the 2 diagonally across from each other hold an equal amount that is more than the lone wire in one corner
c) the lone wire does not support. The 2 diagnoals carry the plate alone.
b) the 2 diagonally across from each other hold an equal amount that is more than the lone wire in one corner
Will an airplane with engine and propeller take off on a treadmill or converyor belt, regardless of the run setting?
Will a glider (no engine or propeller) take off on a treadmill or converyor belt, regardless of the run setting?

A common example of a first-class lever is


a seesaw
a wheelbarrow
tongs
a seesaw

The force F required to balance the weight of 60 lbs on the lever, shown in the diagram above, is most nearly


210 lbs

240 lbs

672 lbs
210 lbs

The mechanical advantage shown is


4

5

8
5

What effort must be exerted to the handles of the wheelbarrow shown carrying a load of 200 lbs (neglect the weight of the wheelbarrow in ur computation)?


40 lbs

50 lbs

65 lbs
50 lbs
The bar, which is exactly 4 inches in length, has a 275 lbs weight on one end and a 125 lb weight on the opposite end. For the bar to balance, the distance from the 275 lb weight to the fulcrum point shd be (neglect the weight of the bar in ur computation)

1 1/4 inches
1 inch
3/4 inches
1 1/4 inches

Neglecting friction, what is the mechanical advantage in using a single fixed pulley as shown ?


1

2

3
1

In the figure shown, the pulley system consists of a fixed block and a moveable block. Neglecting friction and the weight of the pulley system, what effort would be needed to lift a 100 lb weight


100 lbs

75 lbs

50 lbs
50 lbs

The weight W is to be raised as shown in the figure by attaching the pull rope to the truck. If the weight is to be raised 8 ft, the truck will have to move


16 ft

24 ft

32 ft
24 ft

The formula for an inclinded plane is

MA = L/H



MA = mechanical advantage

L = length

H = ?

H = height



MA = L / H

L = length

A gradual slope will provide a ________ mechanical advantage than a steep slope.


higher

lower
higher

In the figure shown, the service person is using a plank to roll a 300-pound barrel up to the bed of the truck. The force that must be applied is most nearly


200 pounds

150 pounds

100 pounds
100 pounds

How do you find the mechanical advantage for a wheel and axel?
Diameter/Radius

In the figure shown, a bucket is being raised by a wheel-and-axel arrangement. If the distance from the center of the axle to the handle is 8 inches and the diameter of the drum around which the rope is wound is 4 inches, the theoretical mechanical advantage is


2

4

8
4

To make a 1/2" hole in a block of wood, use tool



A

B

C
B

To cut a thread on a 1/2" brass rod, use tool


A

B

C
A

The number 18 appearing on the tool shown above indicates



depth of opening

size of opening

threads per inch
threads per inch

Which of the 1½ volt dry cell battery connections shown above will deliver 6 volts?


1

2

3
2

In the figure given, if the thickness of the wall of the pipe is ½", the inside diameter of the pipe is


3"

3 1/8"

3 1/4"
3"

The figure above represents a revolving wheel. The numbers 1 and 2 indicate two fixed points on the wheel. The number 3 indicats the center of the wheel. Of the following, the most accurate statement is that


a) point 1 makes more revolutins per minute than point 2

b) point 2 makes more revolutions per minute than point 1

c) points 1 and 2 make the same number of revolutions per minute
c) points 1 and 2 make the same number of revolutions per minute

In the figure shown, if gear A makes 14 revolutions, gear B will make


14

17

21
21

With the wheels in the position shown in the figure


a) wheels S and T will rotate in opposite direction

b) wheels S and T will rotate in the same directions

c) wheels S and T will rotate at the same speed
b) wheels S and T will rotate in the same directions

In order to open the valve four times every second, the wheel must rotate at


12 rpm

18 rpm

24 rpm

24 rpm


4 times every second = 240

10 rods on the wheel

240/10

In the figure shown, a 160-lb individual jumps off an 800-lb raft to a point in the water 10 ft away. Theoretically, the raft will move


a) 2 ft in the opposite direction

b) 3 ft in the opposite direction

c) 4 ft in the opposite direction
a) 2 ft in the opposite direction

The figure shows a lever-type safety valve. It will blow off at a lower pressure if weight W is


increased

moved to the left

moved to the right
moved to the left

As shown in the figure, four air reservoirs have been filled with air by the air compressor. If the main line air gauge reads 100 lbs, then the tank air gauge will read


25 lbs

50 lbs

100 lbs
100 lbs

In the figure above, the number of complete turns the vise handle must make to fully close the jaws is


14

16

18

20
18

In the figure shown, the center-to-center distance between the two poles is


1 3/4"

1 15/16"

1 7/8"
1 15/16"

If an 8" level indicates 16 quarts of oil in the tank, then the number of quarts of oil to be added to raise the level from 6" to 8" is


2 quarts

4 quarts

6 quarts
4 quarts

Which illustration depicts the compression stroke?


X

Y

Z

Z


Both valves are closed and the piston is moving upwards

What is the proper sequence of the four strokes of a piston in a gasoline engine


W X Y Z

X Z Y W

Y Z X W
Y Z X W

The gauge shown above is a


depth gauge

feeler gauge

thread gauge

thread gauge


The thread or screw-pitch gauge is used to determine the pitch and number of threads per inch of threaded fasteners.

The wrench shown is generally used when


a) a definite force must be applied to a nut or bolt head

b) a tight nut must be broken loose

c) rapid turning of the nut or bolt is of prime importance

a definite force must be applied to a nut or bolt head


The torque is read visually on a dial mounted on the handle of the wrench. It is used when a definte force must be applied.

Which of the figures shown is the proper procedure for pulling adjustable wrenches?


A

B

Both are proper procedures

A


The handle of the adjustable wrench should be pulled toward the side having the adjustable jaw. This will prevent the adjustable jaw from springing open and slipping off the nut.

Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.


True

False
True

Newton's Law describes a relationship between an object's _______ and _______ as the applied force.


pressure, density

weight, velocity

mass, acceleration

density, distance
mass, acceleration

In Newton's Third Law, force


a) is neither created or destroyed

b) if there is no opposing force, the motion will never stop.

c) always elicits an equal, opposite force acting against it

d) is the cause for intertia

e) all of the above

c) always elicits an equal, opposite force acting against it


Whenever a first body exerts a force F on a second body, the second body exerts a force −F on the first body. F and −F are equal in magnitude and opposite in direction.

A 150 lb man jumps off a 600 lb raft to a point in the water 12 ft away. Theoretially, the raft would move


a) 12 ft in the opposite direction

b) 9 ft in the opposite direction

c) 6 ft in the opposite direction

d) 3 ft in the opposite direction

e) 1 ft in the opposite direction

3 ft in the opposite direction



150 lb x 12 ft = 600 lb x ? ft

The mechanical advantage of a lever can be increased by



a) placing the fulcrum closer to the object being lifted

b) moving the effort force upwards the lever closer to the object being lifted

c) lengthening the lever arm or by the placement of the fulcrum (base)

d) both a and c

e) all of the above
d) both a and c

A lever arm is in balance when the force x length of one side of a fulcrum is equal to the force x length on the other side of the fulcrum. With this info, test this concept:


The force F needed to balance the lever is, in lbs, most nearly



10 lbs

14 lbs

15 lbs

18 lbs

10 lbs

Then tension of a string in figure A is greater than the tension of a single spring in Figure B. The spring tension of springs supporting an object individually spreads the load between the individual springs.


10 lb weights are each suspended from a ceiling by 3 identical springs. In A, the extension of each spring is



K) Nine times greater than in B

L) Three times greater than in B

M) The same as in B

N) One-third less than in B

O) One-ninth less than in B
L) Three times greater than in B

Pulleys. Which of the following is always not true about a pulley.



a) a pulley system will reduce the force required to lift an object

b) the mechanical advantage is proportional to the number of moveable and unmoveable pulleys in the system

c) a moveable pulley provides less advantage as a fixed pulley

d) both a and b

e) all of the above
e) all of the above

What amount of force is required to move the weight (assume the supported objects all weight 100 lbs) in the pulley system?
50lbs
What amount of force is required to move the weight (assume the supported objects all weight 100 lbs) in the pulley system? 33.3 lbs
What amount of force is required to move the weight (assume the supported objects all weight 100 lbs) in the pulley system? 25 lbs

The immoveable one pulley system provides ___ the force to lift the object and will have a ratio of 1:1



1/2

1

2

1/2



There is 1 rope. Divided evenly into 2, and no mechanical advantage, since the pulley is immoveable

If the pulley is immoveable, what is the minimum force that must be applied to position 1 in order to raise the 20 lb weight at position 2 upwards 3 feet


20 lbs over 2 ft

10.1 lbs over 3 ft

7.5 lbs over 3 ft
10.1 lbs over 3 ft

This is Boyles Law:



a) Compressing a gas to 1/2 volume doubles the pressure

b) If the pressure decreased by 1/2, the volume would double

c) Both A and B

d) None of the above

c) Both A and B



Actually, Boyle's law describes the inversely proportional relationship between the absolute pressure and volume of a gas, if the temperature is kept constant within a closed system.

Charles' Law is when


a) you heat some liquid, and the temperature changes, but the volume stays the same

b) you open a can of coke, and the soda starts fizzing out

c) both a and b

d) none of the above

b) you open a can of coke, and the soda starts fizzing out



If gas is held at a constant pressure, the volume is directly proportional to the absolute temperature.

Bernoulli's Principal is when


a) a good pitcher throws a curve ball
b) you siphon a gas tank

c) when the pressure increases, the velocity increases

d) both a and b

e) both b and c

d) all of the above

d) both a and b



Bernoulli's princiapl states that as the velocity of a fluid increases, its pressure decreases.



The higher the altitude, the more dense the air.


True

False
False

The deeper an object is submerged, the more pressure is exerted upon it.


True

False
True

Which of the statements about weight are true?


a) Weight is the same closer to the earth's surface as would be in midair

b) Weight is greater on planets with greater mass

c) Weight is consistent from location to location

d) Both A and C

e) All of the above

f) None of the above

b) Weight is greater on planets with greater mass


Mass does not change and is not affected by gravity. Weight does, depending on the location. A and C would apply to Mass, but not weight.

If Gear R is the
driver, at the moment shown, Gear S is


P) not moving

Q) jammed

R) moving at its highest speed

S) moving in the same direction as Gear R

T) moving in the opposite direction as Gear R
T) moving in the opposite direction as Gear R

If Gear A makes 14 revolutions, gear B will make


A) 9 revolutions

B) 14 revolutions

C) 17 revolutions

D) 21 revolutions

E) 25 revoltions
D) 21 revolutions
_______ is the factor or ratio by which a mechanism multiplies the force or torque applied to it.
Mechanical Advantage


Output force

Input force



or



distance w/c force is applied divided by distance over w/c a load is moved