() The two forces F_{1} and F_{2} shown in Fig. 4- 39a and b (looking down) act on a 27.0-kg object on a frictionless tabletop . If F_{1} = 10.2N and F_{2} = 16.0N find the net force on the object and its acceleration for each situation , (a) and (b) .

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 (in m) of a column of water 1.45 km high for a temperature increase of 1.12°c. assume the column is not free to expand sideways. as a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to