The gravitational force exerted on a baseball is 228 N down

The gravitational force exerted on a baseball is 2.28 N down. A pitcher throws the ball horizontally with velocity 16.5 m/s by uniformly accelerating it along a straight horizontal line for a time interval of 181 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? (Enter your magnitude to at least one decimal place.)

magnitude(N)

direction(degrees horizontal axis)

Solution

Gravitational force, F = mg = 2.28 N

So, m = 2.28/9.8 = 0.233 kg

a)

Using the equation of motion,

v = u +at

So, 16.5 = 0 + a*0.181

So, a = 91.16 m/s2

So, distance moved,

s = ut + 0.5*at^2

= 0 + 0.5*91.16*0.181^2

= 1.49 m <--------answer

b)

force on the ball horizontally , Fx = m*a = 0.233*91.16 = 21.24 N

So, magnitude of total force = sqrt(21.24^2 + 2.28^2) = 21.36 N <--------answer

direction = atan(2.28/21.24) = 6.1 deg below the horizontal axis<-----answer