AP Physics C: Unit 3 Practice MC (Shortened)

Front

What is instantaneous power in physics?

Back

Instantaneous power is the rate at which work is done or energy is transferred at a specific moment in time, calculated as the product of force and velocity.

Front

How do you calculate the change in kinetic energy using a force-displacement graph?

Back

The change in kinetic energy is equal to the area under the force vs. displacement graph between two points.

Front

What is the formula for calculating power when moving an object at constant speed against friction?

Back

Power (P) can be calculated using the formula P = F_friction * v, where F_friction is the force of friction and v is the velocity.

Front

What is the average power expended when lifting an object at constant speed?

Back

Average power can be calculated using the formula P = rac{W}{t}, where W is the work done against gravity and t is the time taken.

Front

What is the relationship between work done and kinetic energy?

Back

The work-energy theorem states that the work done on an object is equal to the change in its kinetic energy.

Front

Define kinetic energy and its formula.

Back

Kinetic energy (KE) is the energy an object possesses due to its motion, calculated using the formula KE = rac{1}{2}mv^2, where m is mass and v is velocity.

Front

What is the coefficient of kinetic friction?

Back

The coefficient of kinetic friction (μ_k) is a dimensionless scalar value that represents the frictional force between two moving surfaces divided by the normal force.

Front

How does the mass of an object affect its kinetic energy?

Back

Kinetic energy is directly proportional to the mass of the object; as mass increases, kinetic energy increases for a given velocity.

Front

What is the significance of constant speed in power calculations?

Back

When an object moves at constant speed, the net force acting on it is zero, and the power supplied is equal to the work done against friction or other opposing forces.

Front

Explain the concept of work done against gravity.

Back

Work done against gravity is the energy required to lift an object to a height, calculated as W = mgh, where m is mass, g is acceleration due to gravity, and h is height.