Question

What is the potential energy of a 1.0 kg mass 1.0 m above the ground?

Answer 1

`PE = -9.81 N`

Explanation:

Potential Energy based upon the gravitational force in calculated by the equation

`PE = mgh`

Where
PE = Potential Energy in Newtons `(N = kg*m^2/s^2)`
m = mass in kilograms `(kg)`
g = gravitational acceleration `-9.81 m/s^2`
h = height of the object in meters `(m)`

`PE = ?`
`m = 1.0kg`
`g = -9.81 m/s^2`
`h = 1.0m`

`PE = (1.0kg)(-9.81 m/s^2)(1.0m)`

`PE = -9.81 kg*m^2/s^2`

`PE = -9.81 N`

Answer 2

it depends on what number you have for g

Explanation:

With the method we use in school (In Joules):

Potential energy -> U
U = `m * g * h`
m <- mass of the object
g <- acceleration of gravity
h <- height of the object

if your teacher says g= 9.8 m/ `s^2`
then
U = `1 * 9.8 * 1`
U = 9.8 J

if your teacher says g=10 m/`s^2`
then
U = `1 * 10 * 1`
U = 10 J