Question

What is the potential energy of a 150 kg boulder on a hill that's 40 meters high

Answer 1

`6*10^4 [J]`

Step-by-step explanation:

Gravitational potential energy is given by the formula
`U=mgh` , where

• "U" is the gravitational potential energy,
• "m" is the mass of the object with the energy,
• "g" is the gravitational constant near the surface of the earth, and
• "h" is the height of the object.

Since g = 9.81 m/s^2, substituting the known values into the equation, we can calculate the Potential Energy.

`U=mgh`

Substituting...

`U=(150[kg])(9.81 [(m)/(s^2)])(40[m])`

Calculating and combining units...

`U=58860 [(kg \cdot m^2)/(s^2)]`

This combination of units is a Joule...

`U=58860 [J]`

Note that only 1 significant figure is given for the height, so only 1 significant figure should be used for the final answer:

`U=60,000 [J]` or, in scientific notation
`U=6*10^4 [J]`

Answer 2

Take g=9.8Nkg−1. Q. The gravitational potential energy of a box of weight 150 KGF is 1.5×104J.