Question

A major league pitcher can throw a baseball with a kinetic energy of 150 J. How much work must the pitcher do to the ball to give it that much KE?
A.) 150 J

B.) 0 J

C.) can't tell without knowing the mass of the ball

D.) 75 J

Answer 1

Answer:

A= 150 J

Explanation:

Kinetic energy is the energy of an object in motion.

The formula for kinetic energy is ;

K.E = 1/2 * m *v²  where m is mass and v is velocity

Work done is equal to change in kinetic energy

W= Δ K.E

Given that K.E = 150 J

Taking that the ball was stationary before it was thrown, this makes its initial kinetic energy to be 0 J so the work done will be

W=  Δ K.E

W= 150 - 0

W= 150 J