What Is the Average Force Exerted by the Bat on the Baseball?

[-EquinoX-]

Homework Statement

A 150-g baseball pitched at a speed of 40 m/s is hit straight back to the pitches at a speed of 60 m/s. If the bat is in contact with the baseball for 5 ms calculate the magnitude of the average force exerted by the bat on the baseball.

Homework Equations

Favg = delta p/ delta t

The Attempt at a Solution

delta p = m (Vf-Vi) = 0.150(60-40) = 3
Favg = 3/0.005 = 3

however the answer is 3000N, can anyone clarify where I made the mistake?

 

[alphysicist]

Homework Statement

A 150-g baseball pitched at a speed of 40 m/s is hit straight back to the pitches at a speed of 60 m/s. If the bat is in contact with the baseball for 5 ms calculate the magnitude of the average force exerted by the bat on the baseball.

Homework Equations

Favg = delta p/ delta t

The Attempt at a Solution

delta p = m (Vf-Vi) = 0.150(60-40) = 3

One of the values you have put in for the velocities is not correct. Remember that you have to account for the direction of the ball with the appropriate sign.

 

[-EquinoX-]

oh thanks for pointing that out, it should be 60-(-40)