A 3.0-kg mass is dropped from the edge of a 50-m tall building with an initial speed of zero. The mass strikes the ground with a downward velocity of 25 m/s. Find the change in mechanical energy of the mass caused by air resistance between the point where it is dropped and the point where it strikes the ground?
a. -0.46 kJ
b. -0.53 kJ
c. -0.61 kJ
d. -0.38 kJ
e. -0.81 kJ
B
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