Answer:
88.2 J
Step-by-step explanation:
The formula for GPE (gravitational potential energy) is
GPE = mgh
m (mass) is 3kg
g (acceleration in gravity) is 9.8 m/s^2. This is universal. This value doesn't change ever.
H (height) is 3m because 8m - 5m is 3m. You have to find the difference in height, to find the GPE change for the box.
You plug in all of these values in the formula.
GPE = 3 x 9.8 x 3 = 88.2 J (joules)
Joules the measurment that energy is measured in.