A book has been lifted 1.5 meters into the air giving it 30J of potential energy. How much force was used to lift it

Force on the object is 20 N

Explanation:

As we know that work done to raise the book from initial position to final position is known as potential energy stored in it

So here we know that

here we know that

U = 30 J

s = displacement = 1.5 m

so we have

the answer is a. at the equator