Answer:
(1) 180 J
(2) 60 m/s
Explanation:
(1) From the question,
Amount of work performed by the pitcher on the baseball = Force × distance.
W = F×d............... Equation 1
Given: F = 90 N, Â and d = 2.0 m.
Substitute into equation 1
W = 90×2
W = 180 Joules.
(2)
F = ma........... Equation 2
Where a = acceleration of the ball.
a = F/m
Given: F = 90 N, m = 0.1 kg.
therefore,
a = 90/0.1
a = 900 m/s².
Using,
v² = u² + 2as ............ Equation 3
Where u = 0 m/s, a = 900 m/s², s  = 2 m.
substitute into equation 3
v² = 0² + 2×900×2
v² = 3600
v = √3600
v = 60 m/s