Question

A batter hits a fly ball which leaves the bat 0.89 m above the ground at an angle of 62 ∘ with an initial speed of 29 m/s heading toward centerfield. Ignore air resistance. How far from home plate would the ball land if not caught? The ball is caught by the centerfielder who, starting at a distance of 107 m from home plate, runs straight toward home plate at a constant speed and makes the catch at ground level. Find his speed.

Answer 1

consider the motion in Y-direction

v₀ = initial velocity = 29 Sin62 = 25.6 m/s

a = acceleration = - 9.8 m/s²

t = time of travel

Y = vertical displacement = - 0.89 m

using the equation

Y = v₀ t + (0.5) a t²

- 0.89 = (25.6) t + (0.5) (- 9.8) t²

t = 5.3 sec

consider the motion along the horizontal direction :

v₀ = initial velocity = 29 Cos62 = 13.6 m/s

a = acceleration = 0 m/s²

t = time of travel = 5.3 sec

X = horizontal displacement =?

using the equation

X = v₀ t + (0.5) a t²

X = (13.6) (5.3) + (0.5) (0) t²

X = 72.1 m

d = distance traveled by the center fielder to catch the ball = 107 - x = 107 - 72.1 = 34.9 m

t = time taken = 5.3 sec

v = speed of center fielder

using the equation

v = d/t

v = 34.9/5.3

v = 6.6 m/s