Work and Kinetic Energy Practice

Front

What is kinetic friction?

Back

Kinetic friction is the force that opposes the motion of two surfaces sliding past each other, always acting in the direction opposite to the velocity of the moving object.

Front

Why does kinetic friction always do negative work on a sliding object?

Back

Kinetic friction always points in the direction opposite to an object's velocity, slowing it down and transferring energy from the object to the environment.

Front

What is the work done by gravity on an object moving downward?

Back

Gravity always does positive work on an object that moves downward.

Front

What can be concluded if an object is slowing down?

Back

The sum of work done by each force acting on the object is negative.

Front

What does a graph of kinetic energy look like for an object thrown straight upward?

Back

The graph is a parabola with a minimum, showing kinetic energy decreasing as the object rises and increasing as it falls.

Front

What can be concluded about two forces acting on an object moving with constant speed?

Back

W1 = -W2, meaning the work done by one force is equal in magnitude and opposite in sign to the work done by the other force.

Front

What is the formula for work done by a force?

Back

Work (W) = Force (F) × Displacement (d) × cos(θ), where θ is the angle between the force and the direction of displacement.

Front

What is the principle of conservation of energy?

Back

The total energy in a closed system remains constant; energy can neither be created nor destroyed, only transformed from one form to another.

Front

What is potential energy?

Back

Potential energy is the energy stored in an object due to its position or configuration, commonly associated with gravitational or elastic forces.

Front

How does kinetic energy change as an object falls?

Back

As an object falls, its potential energy decreases while its kinetic energy increases, conserving total mechanical energy in the absence of air resistance.