Author Question: When a Hooke's law spring is stretched a distance 3x, how much is the increase in energy stored in ... (Read 76 times)

maychende · **on:** Jul 28, 2018

When a Hooke's law spring is stretched a distance 3x, how much is the increase in energy stored in it from when it was stretched a distance x? Give your answer in terms of a multiple of the energy stored in the spring when it is stretched a distance x.
a. It is 3 times as much.
c. It is 4 times as much.
b. It is 8 times as much.
d. It is 9 times as much.

Question 2

A Carnot engine runs between a hot reservoir at Th and a cold reservoir at Tc. If one of the temperatures is either increased or decreased by 3.5 K, which of the following changes would increase the efficiency by the greatest amount?
a. increasing Th
b. increasing Tc
c. decreasing Tc
d. cannot be determined from information given