Physics: Hardest Exam! Trivia Quiz

An object 1cm high is placed in front of a converging lens at a distance of  7.5cm from the lens. If the focal length of the lens is 15cm, find the magnification.

• 1

• 2

• 4

• 5

The speed of sound travelling in various media increases in the following correct order:

• Air, water, iron 

• Iron, water, air

• Water, iron, air 

• Iron, water, air

An object of mass of 2kg moving with a velocity of 3ms^-1 collides head-on with another object of mass 1kg moving in the opposite direction with a velocity of 4ms^-1. If the objects stick together after collision, calculate their common speed.

• 0.60 ms<sup style="color: rgb(102, 102, 102); font-weight: inherit;">-1

• 0.67 ms<sup style="color: rgb(102, 102, 102); font-weight: inherit;">-1

• 2.00 ms<sup style="color: rgb(102, 102, 102); font-weight: inherit;">-1 

• 3.33 ms<sup style="color: rgb(102, 102, 102); font-weight: inherit;">-1

A uniform metre rule of mass 0.42kg is balanced at the 60cm mark when a mass m is placed at 90cm mark. Calculate the value of m.

• 0.14kg

• 0.42kg

• 0.82kg

• 0.84kg

The range of a projectile at Ө to the horizontal with a velocity U is given by:

Which of the following instruments produces sound by the vibration of air column?

• Piano

• Guitar

• Flute

• Talking Drum

Dispersion of white light by a glass is due to the

• Defects in the glass

• Different speeds of various colours of light in the glass

• Density of the glass

• Colour of the glass

A constant force acts on a body of mass 50kg and reduces the speed from 90ms^-1 to 20ms^-1 in 20s. Calculate the magnitude of the force.

• 3500N

• 175N

• 875N

• 350N

In which of the following is the speed of sound greatest?

• Air

• Water

• Wood

• Steel

A simple harmonic oscillator has a period of 0.02s and amplitude of 0.25m. Calculate the speed in  ms^-1 at the centre of the oscillation.

• 1.25π

• 25.00π

• 100.00π

• 400.00π

An astronomical telescope with focal length of objective lens, f_o  and eye piece lens, f_e  is in normal adjustment when the final image is formed at infinity. This because

• F₀  >  f_e

• F₀  < f_e

• F₀ - f_e = distance between the two lenses

• F₀ + f_e = distance of the lenses

Sound wave cannot pass through

• Solids

• Liquids

• Vacuum

• Gases

The factor which enables the ear to distinguish between a note played on different instruments is the

• Pitch

• Speed

• Harmonics

• Loudness

A tuning fork of frequency 600HZ is sounded over a closed resonance tube. If the first and second resonant positions are 0.130m and 0.413m respectively. Calculate the speed of sound in air.

• 509.4m/s

• 480.0m/s

• 339.6m/s

• 169.8m/s

If f represents the principal focus of the objective lens of a compound microscope, the object to be viewed should be placed

• At f

• Between f and 2f

• At 2f

• Between f and the objective lens

1. A pipe open at both ends, produces a fundamental note. If the velocity of sound in air is V and Ɩ, the length of the pipe. Which of the following expresses the frequency of the note? (Neglect end – correction).

At the beginning of a race, a tyre of volume 8.0 x 10^-4 m³ at 20⁰C has a gas pressure of 4.5 x 10⁵Pa. Calculate the temperature of the gas in the tyre at the end of the race if the pressure has risen to 4.6 x 10⁵Pa.

• 20⁰C

• 32.5⁰C

• 26.5⁰C

• 50.0⁰C

A lens that is thinner at the middle and thicker at the edges is

• Diverging

• Converging

• Plano-convex

• Converging  meniscus

At which of the following distances from the lens should a slide be placed in a slide projector if f is the focal length of the projection lens:

• Less than f

•  Greater than 2f

• Equal to f

• Greater than f but less than 2f

Primary colours of light are:

• Red, Yellow, Green

• Red, White, Orange

• Red, Blue, Indigo

• Red, Blue, Green.

Which of the following will reduce the frequency of oscillation of a simple pendulum?

• Decreasing the length of the string.

• Increasing the amplitude of oscillation.

• Increasing the length of the string.

• Increasing the mass of the bob.

A simple pendulum with a period of 2.0s has its length doubled. Its new period is

• 0.35s

• 1.00s

• 1.41s

• 2.83s

When white light is passed through a glass prism, it is broken up into its component colours. This phenomenon is known as:

• Reflection

• Diffraction

• Dispersion

• Deviation

Which of the following is a stringed instruments?

• Flute

• Trumplet

• Piano

• Saxophone

Loudness increases as a vibrating tuning fork is brought nearer the end of a pipe containing air column due to

• Resonance

• Echo

• Reverberation

• Diffraction

The radius of a wheel is 30.0cm and that of its axle is 6.0cm. Calculate the effort required to lift a load of 120.0N using this machine, assuming 100% efficiency.

• 600.00N

• 40.0N

• 24.0N

• 20.0N

For a projectile, the maximum range is obtained when the angle  of projectile is:

• 60°

• 30°

• 45°

• 90°

The ability of the eye to focus object at different distances is called:

• Power

•   Accommodation

• Normal vision

•  Persistence of vision

For correcting long sight defects in the human eye, we require a

• Converging lens

• Diverging lens

•  periscope

• Microscope

Which of the following statements about the frequency of a note is correct? As the frequency decreases,

• The velocity increases 

• The pitch decreases 

• The strength increases 

• The loudness decreases.

Which of the following is/are characteristics of sound? I. Pitch   II. Loudness     III. Quality    IV. Noise

• I only 

• II only

• I and II only 

• I,II and III only

An air bubble of volume 4cm³ is formed 20cm under water. What will be its volume when it rises to just below the surface of the water if the atmospheric pressure is equivalent to height of 10cm of water.

• 2cm³

• 4cm³

• 6cm³

• 12cm³

A fixed mass of an ideal gas occupies 1000cm³ at 280mmHg and -73⁰C. Determine  its volume at 760mmHg and 127⁰C.

• 1500cm³

• 1000cm³

• 870cm³

• 578cm³

A block and tackle system has 6 pulleys. If the efficiency of the machine is 60%, determine its mechanical advantage.

• 20.0

• 10.0

• 3.6

• 1.8

1. Two simple pendula A and B of equal lengths and masses 5g and 20g are located in the same environment. The periods T_A and T_B of their respective oscillations are related by the equations

• T_A= 4T_B

• T_A =1/4T_B

• T_A = T_B

• T_A =5T_B

A metre rule AB is pivoted at mid-point C. If a load of mass 2kg is hung  at a point 20cm away from C, the point at which a load of mass 5kg will be hung to balance the rule horizontally is ___.  

• 10.3cm away from C

• 15.5cm away from A 

• 20.0cm away from B

• 26.7cm away from C 

A block an tackle system has six pulleys. A force of 50N applied to it lifts a load of weight W. If the efficiency of the system is 40%, calculate W.

• 300N

• 200N

• 140N

• 120N

Images formed by diverging lenses are always:

• Virtual, enlarged & inverted

• Virtual, diminished and inverted

• Virtual, diminished and erect

• Real, diminished and inverted.

A metre rule is found to balance horizontally at the 48cm mark. When a body of mass 60g is suspended at the 6cm mark, the balance point is found to be at the 30cm mark. Calculate the mass of the metre rule.

• 50g

• 20g

• 80g

• 30g

What part of the camera corresponds to the iris of the eye?

• The shutter

• The film

• The diaphragm

• The lens

Find the focal length of the lens required to correct the defect of vision of a man whose near point is 50cm. Assume the least distance of vision of the normal eye to be 25cm.

• 50cm

• 60cm

• 70cm

• 80cm

A man standing 99m from the foot of a tall cliff claps his hands and hears an echo 0.6s later. Calculate the velocity of sound in air in m/s.

• 59.4 

• 82.5

• 270.0

• 330.0

Which of the following statements about the 3^rd overtones of a vibrating air column of an open pipe is correct? It has

• 4 nodes

• 5 nodes

• 3 antinodes

• 4 antinodes

1. The air column in a resonance tube is set into resonance by a vibrating tuning fork. The resultant waves in the air column will be

• Mechanical and transverse

• Stationary and longitudinal

• Progressive and longitudinal

• Stationary and transverse

A body of mass 80kg moving with a velocity of 6ms^-1 hits a stationary body of mass 40kg. If the two bodies stick together after the collision, calculate the magnitude of the velocity with which they move.

• 4 ms^-1

• 9 ms^-1

• 12 ms^-1

• 16 ms^-1

A plane inclined at an angle of 30⁰ to the horizontal has an efficiency of 60%. A force of magnitude F is used to push a load of 150N up the plane. Calculate F.

• 45N

• 75N

• 125N

• 360N

Image of a distant object is focused before the retina. What defect is this and with what type of lens can it be corrected?

• Short sight, converging lens

• Short sight diverging lens

• Long sight, converging lens

• Long sight, diverging lens

The volume of a given mass of an ideal gas at 327K and 9.52 x 10⁴ Pa is 40cm³. Calculate the volume of the gas at 273K and 034 x 10⁵Pa.

• 68.23cm³

• 47.91cm³

• 44.60cm³

• 30.75cm³