The gravitational force exerted on a baseball is 2.24 N down. A pitcher throws the ball horizontally with velocity 17.0 m/s by u
niformly accelerating it along a straight horizontal line for a time interval of 183 ms. The ball starts from rest. (a) Through what distance does it move before its release?
__________m
(b) What are the magnitude and direction of the force the pitcher exerts on the ball?
magnitude______N
direction_______° above the horizontal
Vertical force = weight of the ball F = ma 2.24 = m x 9.81 mass of ball = 0.23 Kg (a) Acceleration of ball: (v - u)/t = (17 - 0)/0.183 = 92.9 m/s² Using equation of motion: 2as = v² - u², where u is 0 because initially at rest. s = 17²/(2 x 92.9) s = 1.56 m
(b) F = ma = 0.23 x 92.9 = 21.4 N in the direction of motion of the ball tan(∅) = y-component/x-component ∅ = tan⁻¹ (-2.24/21.4) = -5.98° from the horizontal
