If a crane worker lifts a crate with a mass of 120 kg from the ground to a shipping container that is 30 meters off the ground, by how much has the
worker increased the gravitational potential energy of the crate? (Recall that g
= 9.8 m/s2)
A. 46,720 J
B. 35,280 J
C. 29,950 J
D. 18,180 J
SOEM

Explanation:

Given data,

The formula for gravitational potential energy is,

                                 P.E = mgh joules

Substituting the values

                                  P.E = 200 x 9.8 x 45

                                         = 88,200 J

Hence, the gravitational potential energy of the crate is, P.E = 88,200 J

-4 on

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.