Physics

Problem

A trolley of mass

5\,\text{kg}

is moving towards the east with a speed of

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

. A motor fitted to the trolley causes it to speed up to

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

in a straight line during a time interval of

3\,\text{s}

. Neglect any external horizontal forces other than the motor thrust. a. (i) Write the expression for the linear momentum of the trolley at any instant. b. (ii) Calculate the change in momentum of the trolley during the

3\,\text{s}

interval. c. (iii) Determine the magnitude of the average horizontal force exerted by the motor on the trolley in this interval.

Browse the problem library