a popgun uses a spring for which k = 20 N/cm. when cocked, the spring is compressed 3.0 cm. how high can the gun shoot a 5.0-g projectile

Question

drwls · Accepted Answer

Jiskha software automatically censors some words, but I think I know what you mean.
(It rhymes with clocked)

The stored potential in the spring when loaded will be (1/2)kX^2 = (1/2)*20*9 = 90 N-cm = 0.9 Joules

Set 0.90 J = (1/2)M V^2 and solve for V

V = sqrt(2*0.90/.005) = 19.0 m/s

Mike · Answer

Thanks a lot!