Posted by Richard on .
An upright spring which is normally 3 m is compressed 2.3 m and a 2 kg block is placed on it. When it is 5 meters above the ground it is going 10 m/s. What is the spring constant of the spring? How high will the block travel?

Physics 
drwls,
The compressed potential energy of the spring is (1/2) k X^2.
This equals thesum of gravitational poteneital and kinetic energy at any altitude after it is launched.
(1/2) k (3)^2 = (1/2)M V^2 + M g H
V = 10 m/s when H = 5 m
Solve for k
For the additional height it travels, use conservation of energy to determine how much higher it goes when the velocity and KE goes to zero.