Question

A truck of mass 3 tonnes moves up an incline at a constant velocity 10m/s against a frictional force 200 N. The incline is such that it rises 1m for every 15m along the incline. Calculate the power output of the truck engine.(g=10m/s)​

Answer 1

Answer:

22 MW

Velocity is constant , so net force must be zero on truck . Let assume that truck is applying a force of magnitude f in direction of motion .

Since incline rises 1 m for every 15 m , so

$\sin( \alpha ) = \frac{1}{15}$

So balance the forces on truck

$f = mg \sin( \alpha ) + 200 \\ \\ f = 3000 \times 10 \times \frac{1}{15} + 200 \\ \\ f = 2200 \: newton \\ \\ so \\ power = force \times velocity \\ = 2200 \times 10 \\ = 22000 \: watts \\ = 22 \: mwatt$