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A rock weighing 98 newtons is pushed off the edge of a bridge 50 meters above the ground. What was the potential energy of the rock before it began to fall?

User Tim Pesce
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Ep = 4900 because Ep = wh
User Andrewrk
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Answer: The potential energy of the rock before it began to fall is 4900 J

Step-by-step explanation:

Force is defined as the mass multiplied by the acceleration of the object.


F=mg

where,

F = force exerted on the object

m = mass of the object

g = acceleration due to gravity

Potential energy is defined as the energy possessed due to the height of the object.

Mathematically,


E_p=mgh

Or,


E_p=F* h

where,


E_p = potential energy of the rock = ?

F = force applied on the rock = 98 N

h = height of the bridge from where the rock is thrown = 50 m

Putting values in above equation, we get:


E_p=98N* 50m\\\\E_p=4900J

Hence, the potential energy of the rock before it began to fall is 4900 J