Unit 3 - Energy & Conservation (1)

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 = mgh, where m is mass, g is the acceleration due to gravity, and h is height.

Front

How do you calculate gravitational potential energy?

Back

GPE = mgh, where m = mass (kg), g = acceleration due to gravity (9.81 m/s²), and h = height (m).

Front

What is the potential energy of a 20 kg object at a height of 140 m?

Back

GPE = mgh = 20 kg * 9.81 m/s² * 140 m = 27,468 J.

Front

What happens to potential energy as an object descends?

Back

As an object descends, its height decreases, leading to a decrease in gravitational potential energy.

Front

What is mechanical energy?

Back

Mechanical energy is the sum of potential energy and kinetic energy in a system.

Front

How is mechanical energy conserved in a roller coaster?

Back

In a roller coaster, mechanical energy is conserved as potential energy converts to kinetic energy and vice versa, neglecting friction.

Front

What is the potential energy of a 20 kg sphere at a height of 95 m?

Back

GPE = mgh = 20 kg * 9.81 m/s² * 95 m = 18,618 J.

Front

What is the potential energy of a 20 kg sphere at a height of 80 m?

Back

GPE = mgh = 20 kg * 9.81 m/s² * 80 m = 15,696 J.

Front

If a sphere has 28,000 J of potential energy at the top, what happens to its energy at a lower height?

Back

The potential energy decreases as the height decreases, and the lost potential energy converts to kinetic energy.

Front

What is the relationship between height and potential energy?

Back

Potential energy is directly proportional to height; as height increases, potential energy increases.