Question

If 2000 kg cannon fires 2 kg projectile having muzzle velocity 200 m/s then the KINETIC ENERGY of the CANNON will be ("E4" means "*10^4") *

1 point
4 J
40 J
400 J
None of the above

Answer 1

M V = m v conservation of momentum (Caps-cannon Small-projectile)

V = m / M * V = 2 / 2000 * 200 m/s = .2 m/s recoil velocity of cannon

KE = 1/2 M V^2 = 2000 / 2 kg * (.2 m/s)^2 = 40 kg m^2/s^2 = 40 J

Answer 2

40 j would be your answer