A cyclist maintains a constant driving force of against the resistive forces of the…

PHYSICS · Subjective · CBSE · Physics · Work and Energy · Work and Energy

Problem

A cyclist maintains a constant driving force of

150\,\text{N}

against the resistive forces of the road and air. (i) His speed on a level track is

18\,\text{km\,h}^{-1}

. Convert this speed into

\text{m\,s}^{-1}

and calculate the power he develops. (ii) Keeping the same driving force, he now increases his speed to

9.0\,\text{m\,s}^{-1}

. Calculate the new power and find the ratio of the new power to the original power.