Posted by Sarah on .
A spring gun is made by compressing a spring in a tube and then latching the spring at
the compressed position. A 4.97g pellet is placed against the compressed and latched
spring. The spring latches at a compression of 5 cm, and it takes a force of
9.12 N to compress the spring to that point.
(a) If the gun is red vertically, how fast (m/s) is the pellet moving when it loses contact
with the spring?
(b) To what maximum height (m) will the pellet rise? (as measured from the original
latched position)

Physics 
drwls,
The spring constant is
k = 9.12/0.05 = 182.5 N/m
Contact ceases when the compression is x = 0, when no more force is applied by the spring. At that time,
(1/2)kXo^2 = (1/2) m V^2
Xo is the latched compression, 0.05 m.
Solve for V. m must be in kilograms.
2) From the original latched position, add Xo to sqrt(Vo^2)/(2g)