Complete question is;
Two identical books are placed on a bookshelf. Book 1 is on a shelf one meter above the floor and Book 2 is on a shelf two meters above the floor.
Which statement best compares the potential energy of the books.
A) Book 2 has twice as much potential energy as Book 1
B) Book 1 has twice as much potential energy as book 2
Answer:
A: Book 2 has twice as much potential energy as Book 1
Step-by-step explanation:
Formula for potential energy is;
P.E = mgh
Where;
m is mass
g is acceleration due to gravity
h is height
Now, they are identical books and thus will have the same mass while acceleration due to gravity remains constant.
For book 1 which is 1 metre above the floor;
P.E = mg × 1
P.E = mg
For book 2 which is 2 metres above the floor;
P.E = mg × 2
P.E = 2mg
We can see that potential energy for book 2 is twice that of book 1.
Thus,option A is correct.