A professional baseball player runs 21m from centerfield to try and rob a homerun. The baseball player collides with the wall and makes catch 122m away from Homeplate. The player exerts a force of 900N on the wall as he hits it. The wall is flexible and initially bends back by about 0.2m upon collision. However, the wall ultimately snaps back into its original position and is NOT displaced at all. How much work did the player do to the wall?
The work done by the player on the wall can be calculated using the formula:
Work = Force x Distance
In this case, the force exerted by the player on the wall is 900N and the distance over which this force is exerted is the initial displacement of the wall, which is 0.2m. Therefore, the work done by the player on the wall is:
Work = 900N x 0.2m
Work = 180 Joules
So, the player does 180 Joules of work on the wall in order to make the catch.
Jeremy kicks a soccer ball with a force of 250N. Jeremy got a running start and was 2m away from the ball before he made contact. The ball traveled 25m and hit a mailbox with a force of 200N. The mailbox does not move at all, but the ball rolls backwards 3m in the direction of Jeremy. What was the work done by Jeremy to the soccer ball?
*Hint when finding the final distance between Jeremy and the ball to plugin to the equation above, remember that the ball rolled backwards a certain distance after hitting the mailbox.
To calculate the work done by Jeremy on the soccer ball, we need to consider both the initial work done by Jeremy to kick the ball and the work done by the ball as it moves and hits the mailbox.
1. Work done by Jeremy:
Distance = 2m (initial distance between Jeremy and the ball)
Force = 250N
Work = Force x Distance
Work = 250N x 2m
Work = 500 Joules
2. Work done by the ball:
Distance = 25m (distance the ball traveled before hitting the mailbox)
Force = 200N
The ball rolls back 3m after hitting the mailbox, so the final distance between Jeremy and the ball after hitting the mailbox is 25m (initial distance) - 3m (distance rolled back) = 22m.
Work = Force x Distance
Work = 200N x 22m
Work = 4400 Joules
Therefore, the total work done by Jeremy to the soccer ball is the sum of the work he initially did plus the work done by the ball after hitting the mailbox:
Total Work = 500 Joules + 4400 Joules
Total Work = 4900 Joules
So, Jeremy did a total of 4900 Joules of work on the soccer ball.