Meriam, Kraige & Bolton — Kinetics of Particles: Problem 3_252

3/252 A boy of mass $m$ is standing initially at rest relative to the moving walkway, which has a constant horizontal speed $u$. He decides to accelerate his progress and starts to walk from point $A$ with a steadily increasing speed and reaches point $B$ with a speed $\dot{x} = v$ relative to the walkway. During his acceleration he generates an average horizontal force $F$ between his shoes and the walkway. Write the work-energy equations for his absolute and relative motions and explain the meaning of the term $muv$.