U4.A Conservation of Mechanical Energy

Front

What is gravitational potential energy (GPE)?

Back

Gravitational potential energy (GPE) is the energy an object possesses due to its position in a gravitational field, calculated as GPE = mass × gravity × height.

Front

How do you calculate gravitational potential energy?

Back

GPE = mass (kg) × gravitational acceleration (9.81 m/s²) × height (m).

Front

What is kinetic energy?

Back

Kinetic energy is the energy an object has due to its motion, calculated as KE = 0.5 × mass × velocity².

Front

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

Back

The faster an object moves, the more kinetic energy it has, as kinetic energy is proportional to the square of its velocity.

Front

What is the formula for kinetic energy?

Back

KE = 0.5 × mass (kg) × velocity² (m/s)².

Front

If an object has a mass of 2 kg and is moving at a speed of 3 m/s, what is its kinetic energy?

Back

KE = 0.5 × 2 kg × (3 m/s)² = 9 Joules.

Front

What is the relationship between potential energy and height?

Back

Potential energy increases with height; the higher an object is, the more gravitational potential energy it has.

Front

What happens to mechanical energy in a closed system?

Back

In a closed system, the total mechanical energy (kinetic + potential) remains constant, according to the law of conservation of mechanical energy.

Front

What is the law of conservation of mechanical energy?

Back

The law states that in the absence of non-conservative forces (like friction), the total mechanical energy of an object remains constant.

Front

How do you find the mass of an object if you know its gravitational potential energy and height?

Back

Rearrange the GPE formula: mass = GPE / (gravity × height).