Physics: Friction And Force Quiz Questions

Explanation
Friction is a force that acts in the opposite direction to the motion of an object. When an object moves, the surface it is in contact with exerts a resistance force that opposes its motion. This force is known as friction. Therefore, it is correct to say that friction opposes the direction in which an object travels.

Explanation
The correct answer is "displacement / time". Velocity is defined as the rate of change of displacement with respect to time. In other words, it is the distance traveled per unit of time. Therefore, the formula for velocity is displacement divided by time.

Explanation
Acceleration is defined as the rate of change of velocity with respect to time. In other words, it measures how quickly an object's velocity is changing over a given time interval. The formula for acceleration is given by change in velocity divided by the time taken for that change to occur. Therefore, the correct answer is "change in velocity / time".

Explanation
Mass is the correct answer because it refers to the amount of matter in an object. Mass is a fundamental property of an object and is measured in kilograms. It is different from weight, which is the force exerted on an object due to gravity. Friction and force are not directly related to the amount of matter in an object.

Explanation
The correct answer is "rise over run". In physics, acceleration is defined as the rate of change of velocity with respect to time. It is a vector quantity, meaning it has both magnitude and direction. When calculating acceleration, we consider the change in velocity (rise) over the change in time (run). Therefore, the correct formula for acceleration is rise over run.

Explanation
Air resistance is like friction because it opposes the motion of an object through the air. Just like friction between two solid surfaces, air resistance creates a resistance force that acts in the opposite direction of the object's motion. This force increases with the speed of the object and depends on its shape and surface area. Therefore, air resistance can be considered as a form of friction that affects the movement of objects in the air.

Explanation
Forces occur in opposites and equal pairs. This means that for every force exerted on an object, there is an equal and opposite force exerted by the object on another object. This concept is based on Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. In other words, when one object exerts a force on another object, the second object exerts an equal and opposite force on the first object. This principle is fundamental in understanding how forces interact and affect the motion of objects.

Explanation
Hooke's law of elasticity states that the extension of a spring is directly proportional to the load applied to it. This means that as the load increases, the spring will stretch or compress in proportion to the applied force. It is an approximation because it assumes that the spring obeys a linear relationship between the force and the extension, which may not always be true for all materials. However, for most springs within their elastic limit, Hooke's law provides a good approximation of their behavior.