Physics
Physics
Problem
A tennis ball is thrown vertically upward and returns to the thrower's hand after . Take upward direction as positive. State with sign: a. (i) its velocity just after it leaves the hand, b. (ii) its velocity just before it is caught, c. (iii) its average velocity for the whole trip. Explain your answers in one sentence each.Intuitive explanation
The key insight is that symmetry in projectile motion means the upward and downward journeys take equal time. Since the ball returns to its starting height after 4 s total, each half of the trip takes 2 s. Use this to find the initial velocity with , where (gravity acts downward), then determine the sign based on your chosen positive direction.
Intuitive explanation
The key insight is that symmetry in projectile motion means the upward and downward journeys take equal time. Since the ball returns to its starting height after 4 s total, each half of the trip takes 2 s. Use this to find the initial velocity with , where (gravity acts downward), then determine the sign based on your chosen positive direction.