A cricket ball of mass is thrown vertically upward with an initial speed of and…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A cricket ball of mass 150g is thrown vertically upward with an initial speed of 20ms−1 and returns to the point of projection. Neglect air resistance.
(i) Explain with reasons whether the work done by the gravitational force is positive, negative or zero (a) during the ascent, (b) during the descent, and (c) for the complete round trip.
(ii) Using energy considerations, describe qualitatively how the kinetic energy of the ball varies with height during the upward and downward parts of the journey.
(iii) Draw a clearly labelled sketch of kinetic energy versus height for the entire motion, indicating the points of zero and maximum kinetic energy.