A Red Rider bb gun uses the energy in a compressed spring to provide the kinetic energy for propelling a small pellet of mass 0.29 grams. By cocking the lever attached to the stock of the rifle, the spring (k = 1800 N/m) is compressed 9 cm from its equilibrium point.

a. What is the potential energy energy stored in the compressed spring?

b. What is the kinetic energy of the pellet when the spring is released?
J
Remember: If we assume no work is done by non-conservative forces such as friction, then ∆U + ∆K = 0.

c. What is the muzzle velocity of the bb? 263.4930 m/s
If the rifle was modified so that the spring could be compressed twice as far, 18 cm, what would be the resultant muzzle velocity of the bb?
m/s
The Kinetic Energy of the bb is determined by the mass of the bb, m, and the square of velocity; K = 1/2mv2. Incorrect. Tries 1/2 Previous Tries

May someone explain how to do this question?

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