AP Physics Dynamics

Front

What is Newton's Second Law of Motion?

Back

Newton's Second Law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. It can be expressed with the formula F = ma, where F is the net force, m is the mass, and a is the acceleration.

Front

Define free-body diagram.

Back

A free-body diagram is a graphical representation used to visualize the forces acting on an object. It shows the object as a dot and the forces as arrows pointing in the direction of the force, with the length of the arrow representing the magnitude.

Front

What is the coefficient of kinetic friction (μ)?

Back

The coefficient of kinetic friction (μ) is a dimensionless scalar value that represents the ratio of the force of kinetic friction between two bodies to the normal force pressing them together. It quantifies how much frictional force opposes the motion of the objects.

Front

How do you calculate the net force acting on an object?

Back

The net force acting on an object is calculated by vectorially adding all the individual forces acting on the object. If forces are in the same direction, they are added; if they are in opposite directions, they are subtracted.

Front

What is the relationship between mass and acceleration in dynamics?

Back

In dynamics, mass and acceleration are inversely related when a constant force is applied. As mass increases, acceleration decreases for a given force, according to Newton's Second Law (F = ma).

Front

Explain the concept of tension in a rope.

Back

Tension is the force transmitted through a rope, string, or cable when it is pulled tight by forces acting from opposite ends. It is directed along the length of the rope and is equal in magnitude at both ends in a massless rope.

Front

What happens to the forces acting on an object in equilibrium?

Back

In equilibrium, the net force acting on an object is zero. This means that all the forces acting on the object are balanced, resulting in no acceleration.

Front

Define acceleration.

Back

Acceleration is the rate of change of velocity of an object with respect to time. It is a vector quantity, meaning it has both magnitude and direction, and is measured in meters per second squared (m/s²).

Front

What is the principle of action and reaction?

Back

The principle of action and reaction, also known as Newton's Third Law, states that for every action, there is an equal and opposite reaction. This means that if one object exerts a force on another, the second object exerts a force of equal magnitude and opposite direction on the first.

Front

How do you determine the direction of frictional force?

Back

The direction of the frictional force is always opposite to the direction of the motion or the intended motion of the object. It acts to resist the sliding or rolling of one surface over another.