The force required to row a boat at constant velocity is proportional to the speed. If a speed of 4 `kmh^(-1)` requires 7.5 kW, how much power does a speed of 12 `kmh^(-1)` require?

The force required to row a boat at constant velocity is proportional to square of its speed. If a speed of v km/h requires 4 kW, how much power does a speed of 2v km/h require?

The force required to tow boat at a constant velocity is proportional to the velocity. If it takes 7460 W to two a certain boat at a speed of 4 kmph, how much horse power (1 H.P = 746 watts) will be required to tow it at a speed of 12 kmph ? [Hint : Force prop velocity P = force xx velocity]

The force required to tow a car at constant velocity is directly proportional to velocity. If it requires 160 W to two a car with a velocity of 4ms^(-1) , the power it required to move the car with a velocity of 9ms^(-1) is