A rock falls off the top of a cliff of height h. Figure 1 shows the rock falling.
The Earth exerts a force of 150 N on the rock.
rock
cliff
h
150N
Figure 1
The work done by this force when the rock falls from the top to the bottom of the cliff is 2700 J.
(1) Calculate the height, h, of the cliff.

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length of a column of water 1.00 km high for a temperature increase of 1.00ºc. note that this calculation is only approximate because ocean warming is not uniform with depth. (answer in ×10^{-3} −3 m)