6. A motor car, of a total mass 1400 kg, running in
top gear at 55 km/h, passes on to a rsing gradient of 1 in 20 at
that speed. The road and other resistances may be taken as constant
at 270 N/t. With condition unchanged, the speed falls uniformly to
40 km/h in a distance of 360 m. An intermediate gear is then
engaged for which the speed ratio between the engine and the road
wheels is 9:1 and...