posted by Anonymous .
A 5 Kg marble is fired vertically upward using a spring gun. The spring must be compressed 8.0cm if the marble is to just reach a target 20m above the marble’s position on the compressed spring.
a) What is the change ∆U in the gravitational potential energy of the marble-Earth system during the 20m ascent?
b) What is the change in ∆U in the elastic potential energy of the spring during its launch of marble?
c) What is the spring constant of the spring?
I am sure that you know by now the formulas for gravitational potential energy and the potential energy of a compressed spring.
The two P.E.s are equal in this case.