A student analyses the vertical motion of a ball that is projected vertically upward…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A student analyses the vertical motion of a ball that is projected vertically upward from ground level with an initial speed of 20m/s. The student chooses the upward direction as positive and neglects air resistance.
(a) Part 1: (i) At three instants—(a) the moment of projection, (b) the highest point of the flight, and (c) just before the ball returns to ground level—state the sign (positive, negative, or zero) of each of the following physical quantities:
(1) displacement from the point of projection,
(2) velocity,
(3) acceleration.
(b) Part 2: (ii) Give a brief explanation for every sign you have assigned in part (i).