Test – Kinetic Energy and Gravitational Potential Energy

A car with a mass of 1200 kg is traveling at a speed of 25 m/s. Calculate its kinetic energy.

A book with a mass of 1.5 kg is placed on a shelf 2 meters above the ground. Calculate the gravitational potential energy of the book relative to the ground. (g = 9.8 N/kg)

Explain why the kinetic energy of an object quadruples when its speed doubles.

A ball with a mass of 0.3 kg is thrown vertically upward with a speed of 12 m/s. Calculate:

1. The initial kinetic energy of the ball
2. The maximum height the ball will reach (ignore air resistance)
3. The gravitational potential energy at the maximum height

A roller coaster car with a mass of 800 kg is at the top of a 45 m high hill. Calculate:

1. The gravitational potential energy at the top of the hill
2. If all this energy is converted to kinetic energy at the bottom of the hill, what will be the speed of the car? (Ignore friction and air resistance)

A pendulum consists of a 0.2 kg mass attached to a string. When the pendulum is released from rest, the mass swings through its lowest point at a speed of 2.5 m/s. Calculate:

1. The kinetic energy of the mass at its lowest point
2. The height from which the pendulum was released, relative to its lowest point (ignore friction, g = 9.8 N/kg)

A cyclist and bicycle have a combined mass of 90 kg. The cyclist does 4500 J of work to accelerate from rest. Calculate the final speed of the cyclist.

An object with a mass of 5 kg is dropped from a height of 8 m. Calculate:

1. The initial gravitational potential energy
2. The kinetic energy just before it hits the ground (ignore air resistance)
3. The speed of the object just before it hits the ground

A student with a mass of 60 kg runs up a flight of stairs that is 4 m high in 6 seconds. Calculate:

1. The gravitational potential energy gained by the student
2. The power developed by the student (Power = Energy ÷ Time)

A spring-loaded toy gun fires a 0.05 kg plastic ball horizontally. If the ball leaves the gun with a speed of 15 m/s, calculate:

1. The kinetic energy of the ball
2. If the ball is fired at a height of 1.2 m above the ground, calculate its kinetic energy just before it hits the ground (ignore air resistance)
3. Calculate the speed of the ball just before it hits the ground