Asked by grace

tommy builds a human sling shot that has an elastic constant of 4000 N/m. He puts his little sister in it and pulls it back for 5 meters. How much energy does his 25 kg sister have as she leaves the sling shot and how fast is she flying?
Answered by drwls
The stored potential energy in the elastic material is (1/2)kX^2 = 50,000 J. That gets converted to kinetic energy when the sister is released.

Set (M/2)V^2 = 50,000 J and solve for V.

The answer I get is too fast to be safe.
Answered by amy
No i'm pretty sure you are right, thank you!!!