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?

1 Answer
Jan 6, 2017

#4900J#

Explanation:

Gravitational potential energy is always measured relative to an origin. So in this case if ground level is taken as # GPE=0 J#

the GPE of the rock is calculated by the formula

#GPR=mgh#

#mg" "# is the wieght

so #GPE=98xx50=4900 J#