A car is traveling along a flat, straight highway with a speed of' 25 meters per second. If the car's engine provides a forward
force of 2,250 Newtons, calculate the force of friction acting on
the car. (F = ma)

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

(a) if the pressure in gas is doubled while its volume is held constant, by what factor do (i) vrms and (ii) change? (b) is it possible to boil water at room temperature (20oc) without heating it? explain.

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