Energy and Momentum Review

Front

What is the unit for energy and work?

Back

J (Joules)

Front

What happens to the momentum of an object when its speed is doubled?

Back

The momentum doubles.

Front

What is the formula to calculate gravitational potential energy?

Back

Potential Energy (PE) = mass (m) × gravity (g) × height (h)

Front

If a 40 kg crate is lifted to a height of 50m, what is its gravitational potential energy?

Back

PE = 40 kg × 9.8 m/s² × 50 m = 19600 J

Front

What is the velocity of a 40 kg crate just before it hits the ground after falling from 50m?

Back

31.3 m/s

Front

What type of energy does a dropped object have just before it hits the ground?

Back

Kinetic Energy

Front

What is the formula for calculating kinetic energy?

Back

Kinetic Energy (KE) = 0.5 × mass (m) × velocity (v)²

Front

If a 5 kg ball is lifted 12 m above the ground, what is its gravitational potential energy?

Back

PE = 5 kg × 9.8 m/s² × 12 m = 588 J (approximately 600 J)

Front

What is the relationship between work and energy?

Back

Work done on an object results in a change in its energy.

Front

What is the principle of conservation of momentum?

Back

In a closed system, the total momentum before an event is equal to the total momentum after the event.