1.
_______: Law of intertia
Correct Answer
Newton's 1st law of motion
Explanation
The given answer, "Newton's 1st law of motion," is the correct explanation for the statement "Law of inertia." Newton's 1st law of motion states that an object at rest will remain at rest, and an object in motion will continue moving at a constant velocity unless acted upon by an external force. This law is also known as the law of inertia, which describes the tendency of objects to resist changes in their state of motion.
2.
_______: Changes in angular momentum
Correct Answer
torque
Explanation
Torque is the correct answer because it is directly related to changes in angular momentum. Torque is the rotational equivalent of force, causing an object to rotate around an axis. When a torque is applied to an object, it can cause a change in its angular momentum, which is a measure of how fast an object is rotating. Therefore, changes in angular momentum can be attributed to the presence of torque.
3.
_______: mg
Correct Answer
weight
Explanation
The given information is incomplete and not readable. It is not clear what the missing word or phrase is. Therefore, an explanation cannot be provided.
4.
_______: Required for an object to float
Correct Answer
buoyant force
Explanation
The buoyant force is the upward force exerted by a fluid on an object submerged in it or floating on its surface. It is the force that opposes the weight of the object and allows it to float. The buoyant force is dependent on the density of the fluid and the volume of the object. When the buoyant force is greater than or equal to the weight of the object, it will float. Therefore, the buoyant force is necessary for an object to float.
5.
_______: mvr
Correct Answer
angular momentum
Explanation
The given statement is incomplete as it only mentions "mvr", which is a formula used to calculate the angular momentum of an object in rotational motion. Angular momentum is a property of rotating objects and is defined as the product of the moment of inertia and the angular velocity of the object. Therefore, the correct answer is "angular momentum".
6.
_______: Mass x velocity
Correct Answer
linear momentum
Explanation
Linear momentum is defined as the product of an object's mass and its velocity. It is a vector quantity that represents the motion of an object in a straight line. The greater the mass or velocity of an object, the greater its linear momentum. Therefore, the given answer correctly states that linear momentum is equal to mass multiplied by velocity.
7.
_______: F = ma
Correct Answer
Newton's 2nd law of motion
Explanation
The given answer, "Newton's 2nd law of motion," is the correct explanation for the equation F = ma. This equation represents Newton's 2nd law of motion, which states that the force acting on an object is equal to the mass of the object multiplied by its acceleration. This law helps to understand how forces affect the motion of objects and is a fundamental principle in physics.
8.
_______: Conservation law requiring the absence of an unbalanced torque
Correct Answer
law of conservation of angular momentum
Explanation
The given answer, "law of conservation of angular momentum," is correct because it accurately describes a conservation law that requires the absence of an unbalanced torque. The law of conservation of angular momentum states that the total angular momentum of a closed system remains constant unless acted upon by an external torque. This means that if there is no net external torque acting on a system, the total angular momentum of the system will remain constant over time.
9.
_______: Action and reaction
Correct Answer
Newton's 3rd law of motion
Explanation
Newton's 3rd law of motion states that for every action, there is an equal and opposite reaction. This means that when an object exerts a force on another object, the second object will exert a force of equal magnitude but in the opposite direction on the first object. This law explains the relationship between two interacting objects and how their forces are related.
10.
_______: Capable of producing motion or a change in motion
Correct Answer
force
Explanation
Force is defined as the capability to produce motion or a change in motion. It is a physical quantity that can cause objects to accelerate or decelerate. In other words, force is the push or pull exerted on an object to make it move or alter its current state of motion. It is measured in units called Newtons (N) and can be applied in various forms such as gravity, friction, or applied forces by humans or machines.
11.
_______: Universal constant
Correct Answer
G
Explanation
The given answer "G" is a universal constant. It is commonly known as the gravitational constant and is denoted by the symbol "G". This constant appears in the equation for Newton's law of universal gravitation, which describes the force of gravitational attraction between two objects. It has a fixed value and is used in various calculations related to gravity and celestial mechanics.
12.
_______: SI unit of force
Correct Answer
newton
Explanation
The SI unit of force is called the newton. This unit is named after Sir Isaac Newton, who made significant contributions to the field of physics and formulated the laws of motion. The newton is defined as the force required to accelerate a one-kilogram mass by one meter per second squared. It is widely used in various scientific and engineering disciplines to quantify and measure forces.
13.
_______: Resistance of relative motion
Correct Answer
friction
Explanation
Friction is a force that opposes the relative motion between two surfaces in contact. It is caused by the irregularities on the surfaces that interact, resulting in resistance to motion. Friction can be experienced in various situations, such as when walking on the ground or when objects slide against each other. It plays a crucial role in our daily lives, as it allows us to grip objects, control vehicles, and walk without slipping. Therefore, friction is the correct answer to the given question.
14.
_______: A nonzero vector sum of forces
Correct Answer
unbalanced force
net force
Explanation
An unbalanced force refers to a nonzero vector sum of forces acting on an object. This means that the forces are not canceling each other out and there is a resulting net force. The net force is the overall force acting on an object, taking into account the magnitude and direction of all the individual forces. Therefore, both unbalanced force and net force are correct terms to describe a nonzero vector sum of forces.
15.
_______: Occurs in the absence of an unbalanced force
Correct Answer
law of conservation of linear momentum
Explanation
The given statement refers to a phenomenon that occurs when there is no unbalanced force acting on an object. This is known as the law of conservation of linear momentum. According to this law, the total momentum of a system remains constant if no external forces are acting on it. In other words, if the net external force on a system is zero, the total momentum of the system will remain unchanged. This principle is widely used in physics to analyze and understand the motion of objects and systems.
16.
_______: Describes the force of gravity
Correct Answer
Newton's law of universal gravitation
Explanation
Newton's law of universal gravitation describes the force of gravity between two objects. It states that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. This law explains the gravitational force that exists between any two objects, regardless of their size or distance from each other.
17.
_______: A measure of inertia
Correct Answer
mass
Explanation
Mass is a measure of inertia because it quantifies the resistance an object has to changes in its motion. Inertia refers to an object's tendency to maintain its state of motion, whether it is at rest or in motion. The greater the mass of an object, the more difficult it is to change its velocity or direction. Therefore, mass can be seen as a measure of how much force is required to accelerate an object or to stop its motion.
18.
_______: Gives the magnitude of the buoyant force
Correct Answer
Archimedes' principle
Explanation
Archimedes' principle states that an object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid displaced by the object. This principle explains why objects float or sink in fluids. The magnitude of the buoyant force is determined by the weight of the fluid displaced, which is equal to the weight of the object when it is fully submerged. Therefore, Archimedes' principle gives the magnitude of the buoyant force.
19.
What is the state of an object being acted upon by an unbalanced force?
Correct Answer
C. Accelerated
Explanation
When an object is being acted upon by an unbalanced force, it means that the net force acting on the object is not zero. According to Newton's second law of motion, an unbalanced force causes an object to accelerate. Therefore, the correct answer is "accelerated".
20.
What is a possible state of an object in the absence of a net force?
Correct Answer
D. All of these
Explanation
In the absence of a net force, an object can be in a state of rest (not moving), constant speed (moving at a consistent velocity), or zero acceleration (not changing its velocity). Therefore, all of these options are possible states for an object when there is no net force acting on it.
21.
What term refers to the tendency of an object to remain at rest or in uniform, straight-line motion?
Correct Answer
D. All of these
Explanation
The term that refers to the tendency of an object to remain at rest or in uniform, straight-line motion is inertia. Inertia is the property of matter that resists changes in its state of motion. It is directly related to an object's mass, as objects with more mass have more inertia. Additionally, force is also related to inertia, as a force is required to overcome an object's inertia and cause it to accelerate or change its motion. Therefore, all of these options - mass, force, and inertia - are correct in describing the tendency of an object to remain at rest or in uniform, straight-line motion.
22.
What is necessary for a change in velocity?
Correct Answer
B. An unbalance force
Explanation
A change in velocity requires an unbalanced force. This means that there must be a force acting on an object that is not being counteracted by an equal and opposite force. When there is an unbalanced force, it can cause the object to accelerate or decelerate, resulting in a change in velocity. Inertia, a zero net force, and a change in direction are not necessarily required for a change in velocity to occur.
23.
A change in which of the following affects the weight of an object?
Correct Answer
B. Accelration due to gravity
Explanation
Acceleration due to gravity affects the weight of an object. Weight is the force exerted by gravity on an object, and it is directly proportional to the acceleration due to gravity. In other words, the weight of an object increases or decreases depending on the strength of the gravitational pull on it. Therefore, a change in acceleration due to gravity will result in a corresponding change in the weight of the object.
24.
For every action force, there is which of the following?
Correct Answer
D. An equal and opposite force
Explanation
According to Newton's third law of motion, for every action force, there is an equal and opposite reaction force. This means that whenever an object exerts a force on another object, the second object exerts a force of the same magnitude but in the opposite direction on the first object. This principle ensures that forces always occur in pairs, and the two forces act on different objects. Therefore, the correct answer is "an equal and opposite force."
25.
Which is true of the force pair of Newton's third law?
Correct Answer
B. The two forces act on different objects.
Explanation
Newton's third law states that for every action, there is an equal and opposite reaction. This means that when one object exerts a force on another object, the second object exerts an equal and opposite force on the first object. Therefore, the force pair in Newton's third law always involves two forces acting on different objects.
26.
Which is true about the acceleration due to gravity?
Correct Answer
C. It decreases with increasing altitude.
Explanation
The acceleration due to gravity is the force that attracts objects towards the center of the Earth. As altitude increases, the distance between an object and the Earth's center also increases. This means that the gravitational force acting on the object decreases, resulting in a decrease in the acceleration due to gravity. Therefore, the statement "It decreases with increasing altitude" is true.
27.
What is true about the constant G?
Correct Answer
A. It is a very small quantity.
Explanation
The constant G, also known as the gravitational constant, is a very small quantity. It is a fundamental constant in physics that determines the strength of the gravitational force between two objects. It is approximately equal to 6.674 × 10^-11 N(m/kg)^2. The small value of G indicates that the gravitational force is relatively weak compared to other fundamental forces, such as the electromagnetic force.
28.
If a submerged object displaces an amount of liquid with a weight less than its own, when the object is release, it will.....
Correct Answer
A. Sink
Explanation
When a submerged object displaces an amount of liquid with a weight less than its own, it means that the object is denser than the liquid. This density difference causes the object to experience a greater downward force than the upward buoyant force exerted by the liquid. As a result, the object will sink when it is released, moving downwards until it reaches the bottom of the liquid.
29.
A change in linear momentum requires which of the following:
Correct Answer
D. All of these
Explanation
A change in linear momentum requires all of these factors. When an object's momentum changes, it means there is a change in its velocity, which is the rate of change of its displacement. This change in velocity can be caused by an unbalanced force acting on the object, which is necessary to accelerate it. Therefore, all of these factors are required for a change in linear momentum to occur.
30.
Angular momentum is conserved in the absense of which of the following?
Correct Answer
C. A net torque
Explanation
Angular momentum is a property of rotating objects that remains constant unless acted upon by an external force. When there is no net torque acting on an object, its angular momentum is conserved. In this case, the correct answer is "a net torque" because the absence of a net torque means that there are no external forces causing a change in the object's rotational motion, and therefore its angular momentum remains constant.
31.
A force is a quantity that is __________ of producing motion or a change in motion.
Correct Answer
capable
Explanation
A force is a quantity that is capable of producing motion or a change in motion. This means that a force has the ability or potential to cause an object to move or to alter its current state of motion. Forces can be exerted on objects in various ways, such as pushing, pulling, or gravitational attraction. The concept of "capable" implies that a force has the power or capacity to bring about a change in motion, highlighting the fundamental role of forces in the study of physics.
32.
Forces are __________ quantities.
Correct Answer
vector
Explanation
Forces are vector quantities because they have both magnitude and direction. This means that in order to fully describe a force, we need to know how strong it is (magnitude) and in which direction it is acting. Vector quantities can be represented by arrows, where the length of the arrow represents the magnitude of the force and the direction of the arrow represents the direction of the force.
33.
Galileo concluded that objects __________ (could/could not) remain in motion without a net force.
Correct Answer
could
Explanation
Galileo concluded that objects could remain in motion without a net force. This means that according to Galileo's observations and experiments, objects can continue to move without any external force acting upon them. This idea challenged the prevailing belief at the time that a force was necessary to keep an object in motion. Galileo's conclusion was a significant contribution to the understanding of motion and laid the foundation for Newton's laws of motion.
34.
An object will not remain at rest or in uniform, straight-line motion if acted upon by a(n) __________ force.
Correct Answer
net
unbalanced
Explanation
When an object is acted upon by a net or unbalanced force, it means that the total force acting on the object is not zero. This causes a change in the object's state of motion. If the object is initially at rest, it will start to move. If the object is already in motion, its speed or direction of motion will change. In both cases, the object will not remain at rest or continue in its original straight-line motion. Therefore, the correct answer is net, unbalanced.
35.
Mass is a measure of __________.
Correct Answer
Explanation
Mass is a measure of the amount of matter in an object. It is a fundamental property of matter and is commonly measured in units such as kilograms or grams. Mass does not change with the location of the object or the force applied to it, making it different from weight, which is dependent on the gravitational pull on the object. Mass is an important concept in physics and is used to calculate various properties and quantities, such as inertia and momentum.
36.
According to Newton's second law, an object's acceleration is __________ proportional to its mass.
Correct Answer
inversely
Explanation
According to Newton's second law, an object's acceleration is inversely proportional to its mass. This means that as the mass of an object increases, its acceleration decreases, and vice versa. In other words, if you double the mass of an object, its acceleration will be halved. This relationship is described by the equation F = ma, where F is the force applied to the object, m is its mass, and a is its acceleration.
37.
The newton unit of force is equal to __________ in standard units.
Correct Answer
kg*m/s^2
(kg)(m/s^2)
Explanation
The newton unit of force is equal to kg*m/s^2 or (kg)(m/s^2) in standard units. This is because the newton is defined as the amount of force required to accelerate a mass of one kilogram by one meter per second squared. Therefore, the unit of force is a combination of the units for mass (kg), distance (m), and time (s) squared.
38.
The coefficient of __________ friction is generally greater than the coefficient of __________ friction.
Correct Answer
static
kinetic
Explanation
The coefficient of static friction is generally greater than the coefficient of kinetic friction. This is because static friction is the force that prevents an object from moving when a force is applied to it. It requires more force to overcome this friction and start the object in motion. On the other hand, kinetic friction is the force that opposes the motion of an object already in motion. Once the object is in motion, it requires less force to keep it moving compared to the force required to overcome static friction.
39.
Newton's third-law force pair act on __________ objects.
Correct Answer
different
Explanation
Newton's third law of motion states that for every action, there is an equal and opposite reaction. This means that whenever an object exerts a force on another object, the second object exerts an equal and opposite force on the first object. These forces, known as the third-law force pair, always act on different objects. In other words, if object A exerts a force on object B, then object B exerts an equal and opposite force on object A. Therefore, the correct answer is "different."
40.
The universal gravitational constant is denoted by the symbol __________.
Correct Answer
G
Explanation
The universal gravitational constant is denoted by the symbol "G". This constant is a fundamental constant in physics that appears in the law of universal gravitation, which describes the force of gravity between two objects. The value of G is approximately 6.67430 × 10^-11 N(m/kg)^2, and it is used to calculate the gravitational force between any two objects in the universe.
41.
An object will sink in a fluid if its average density is __________ than that of the liquid.
Correct Answer
greater
Explanation
An object will sink in a fluid if its average density is greater than that of the liquid because the buoyant force acting on the object will be less than its weight. This causes the object to experience a net downward force, leading to sinking.
42.
Milk is __________ dense than the cream that floats on top.
Correct Answer
more
Explanation
Milk is more dense than the cream that floats on top because density is a measure of how much mass is packed into a given volume. Since milk contains more solids and proteins than cream, it has a higher density. This causes the cream, which is less dense, to rise to the top.
43.
The total linear momentum is not conserved if there is a(n) __________ force acting on the system.
Correct Answer
net
unbalanced
Explanation
If there is a net or unbalanced force acting on the system, the total linear momentum is not conserved. This is because a net force causes an acceleration, which in turn changes the velocity of the system. According to Newton's second law of motion, the change in velocity is directly proportional to the net force applied. Therefore, if there is a net or unbalanced force, the total linear momentum of the system will change over time, indicating that it is not conserved.
44.
The angular momentum of an object is not conserved if the object is acted upon by an unbalanced __________.
Correct Answer
torque
Explanation
The angular momentum of an object is a measure of its rotational motion and is conserved when there is no external influence. However, if the object is acted upon by an unbalanced torque, which is a force that causes rotation, the angular momentum will not be conserved. Torque can change the object's rotational speed or direction, causing a change in its angular momentum. Therefore, the correct answer is torque.