adree
Answered

Discover the answers to your questions at Westonci.ca, where experts share their knowledge and insights with you. Ask your questions and receive accurate answers from professionals with extensive experience in various fields on our platform. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

A baseball of mass 250g, pitched with a speed of 40m/s is caught by the catcher, whose glove moves backward 0.25m while stopping the ball. What was the kinetic energy of the ball before it was caught?

Sagot :

The kinetic energy is =.5mv^2 so the amount the glove moved beforehand is irrelevant and typically this is measured in Kgm/s so 250g is .25kg and v^2 is 40x40 so 1600 lastly 1600x.5x.25 is 200kgm/s :)
AL2006

I don't think we care about the motion of the catcher's glove. 

The mass of the ball is 0.25kg and its speed is 40m/s. 
So its kinetic energy is . . .

     KE = 1/2 (mass) (speed)² =
 
               (0.125 kg) (40m/s)² =

                        200 kg-m²/s² = 200 joules .