Gravitational Potential Energy Flashcards

All 5 cards in this deck

What is the equation for the gravitational potential energy gained by an object raised above ground level?

$E_p = mgh$ (mass × gravitational field strength × height)

In $E_p = mgh$, what is $g$ and what are its units?

Gravitational field strength, in newtons per kilogram (N/kg); about 9.8 N/kg on Earth.

What are the steps to calculate the gravitational potential energy gained by a lifted object?
e.g. a 2 kg mass raised 5 m, $g = 9.8$ N/kg

1. Write $E_p = mgh$
2. Substitute: $2 \times 9.8 \times 5$
3. $E_p = 98$ J

What are the steps to find the height an object was raised from its gain in gravitational potential energy?
e.g. $E_p = 196$ J, mass 2 kg, $g = 9.8$ N/kg

1. Rearrange: $h = \dfrac{E_p}{mg}$
2. Substitute: $h = \dfrac{196}{2 \times 9.8}$
3. $h = 10$ m

True or false? In $E_p = mgh$, $h$ is the distance moved along a slope.

False. $h$ is the vertical height gained or lost.