A rock with a mass of 500 grams drops to the ground from a height of 30.0 meters. What is the decrease in the GPE of the rock, in joules?
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Answer:
Decrease in GPE = 147.15 joules
Explanation:
To calculate for GPE we use the following equation.
GPE = mgh
Where
M= mass in (kg)
g = acceleration due to gravity in m/s²
H = height in meters
The object fell to the ground which means it exhausted it's energy.
At stage1
Before it was released
The potential energy
GPE = ( 500/1000)*9.81*30
GPE = 0.5*9.81*30
GPE= 147.15 JOULES
stage 2
When it hits ground
No height to travel so h= 0.
GPE = Mgh
GPE = 0.5*9.81.0
GPE= 0
Decrease in GPE = 147.15-0
Decrease in GPE = 147.15 joules