Unit 3: Work, Energy and Power

A 2 kg ball is dropped from a height of 5 m. What is its speed just before hitting the ground? (g = 10 m/s²)

A spring with k = 200 N/m is compressed 0.1 m. How much elastic potential energy is stored?

A 5 kg object is lifted 3 m vertically. The work done against gravity is (g = 10 m/s²)

A spring with spring constant k = 200 N/m is compressed 0.1 m. The elastic potential energy stored in the spring is

A roller coaster car (mass 500 kg) starts from rest at the top of a 40 m hill and reaches the bottom. If 20% of the energy is lost to friction, its speed at the bottom is approximately

The kinetic energy of a 2 kg object moving at 3 m/s is

A force of 100 N is applied at a 60° angle to the horizontal to push a box 5 m along a horizontal floor. The work done by the force is

An engine does 6000 J of work in 2 seconds. The power output is

A 0.5 kg ball is dropped from a height of 5 m. Just before hitting the ground, its kinetic energy is (assuming no air resistance, g = 10 m/s²)

If the speed of an object is tripled, its kinetic energy is multiplied by

A 2 kg ball is dropped from 20 m. If 20% of its energy is lost to air resistance, its speed just before hitting the ground is (g = 10 m/s²)

A car engine produces 5000 W of power. How much work does it do in 2 minutes?

A 0.5 kg ball is thrown straight up at 20 m/s. Using energy conservation, the maximum height reached is (g = 10 m/s²)

A roller coaster car of mass 500 kg is at the top of a 40 m hill. Its speed at the bottom of the hill, assuming no friction, is (g = 10 m/s²)

A 1500 kg car goes around a circular turn of radius 50 m at 20 m/s. What centripetal force is needed?

If you triple the distance between two objects, the gravitational force between them:

For a car turning on a flat road, the centripetal force is provided by:

An object completes one full revolution of radius 10 m in 4 seconds. What is its speed?

A satellite in orbit around Earth is held in orbit by:

If the mass of one object in a gravitational interaction is doubled, the gravitational force:

An astronaut orbiting Earth feels "weightless" because:

The centripetal acceleration of an object moving in a circle points:

At what altitude above Earth's surface is the gravitational field strength ¼ of its surface value?

At the top of a vertical circle, the minimum speed for the object to maintain circular motion is when the centripetal force equals:

Planet X has twice the mass and twice the radius of Earth. What is the surface gravity on Planet X compared to Earth?

A ball on a string moves in a horizontal circle. If the string breaks, the ball:

According to Kepler's second law, a planet moves:

If a car doubles its speed on a curve of the same radius, the required centripetal force:

How much work is done by the applied force?

What is the final speed of the block?

What is the speed of the ball at the bottom of the ramp?

What is the power output of the motor?

What is the maximum speed of the block after release?

What percentage of the initial energy is lost to friction?

How much work is done by the force as the object moves from x = 0 to x = 6 m?

If the reference point for PE is the ground, what is the gravitational PE at position B?

What is the efficiency of the motor?

Which object has the greatest kinetic energy?

A 0.50 kg ball is attached to a string and swings as a pendulum. It is released from rest at a height of 0.80 m above its lowest point. What is the speed of the ball at the lowest point? (g = 10 m/s²)

A spring with spring constant k = 200 N/m is compressed 0.10 m and then used to launch a 0.050 kg ball vertically. Assuming no energy is lost, what is the maximum height reached by the ball? (g = 10 m/s²)

A roller coaster car (mass 500 kg) starts from rest at the top of a 40 m hill and passes through a loop of radius 10 m. What is the speed of the car at the top of the loop? (g = 10 m/s², ignore friction)

A 1000 kg car brakes from 30 m/s to 10 m/s. How much kinetic energy is lost?

A spring with spring constant 200 N/m is compressed 0.3 m. A 0.5 kg ball is placed against it and released on a frictionless surface. What is the ball's speed when it leaves the spring?