Question

A 7.50kg laundry bag is dropped from rest at an initial height of 3.00 m. What is the potential energy of the bag when it is at a height of 2.00 m?

1) 0 J
2) 15 J
3) 22.5 J
4) 30 J

Answer 1

The potential energy of the bag when it is at a height of 2.00 m is 147 J.

Step-by-step explanation:

The potential energy of an object at a certain height is given by the equation PE = mgh, where m is the mass, g is the acceleration due to gravity, and h is the height. In this case, the mass of the bag is 7.50 kg and the initial height is 3.00 m. So, the initial potential energy of the bag is PE = (7.50 kg)(9.8 m/s^2)(3.00 m) = 220.5 J.

When the bag is at a height of 2.00 m, we can use the same equation to calculate the potential energy. So, the potential energy of the bag when it is at a height of 2.00 m is PE = (7.50 kg)(9.8 m/s^2)(2.00 m) = 147 J.

Therefore, the potential energy of the bag when it is at a height of 2.00 m is 147 J, which corresponds to option 3) 22.5 J.