Answer:
The muzzle speed of the bullet = 360 m/s
Explanations:
Mass of the bullet, m = 0.025 kg
Length of the rifle, d= 0.45 m
Force on the bullet, F = 3600 N
Workdone on the bullet (W) = Force on the bullet (F) x Length of the rifle(d)
W = Fd
W = 3600 x 0.45
W = 1620 Joules
Kinetic energy of the bullet, KE = 0.5mv²
where v is the speed that the bullet leaves the gun barrel
KE = 0.5 x 0.025 x v²
KE = 0.0125v²
Workdone on the bullet = Kinetic Energy on the bullet
W = KE
1620 = 0.0125v²
v² = 1620/0.0125
v² = 129600
v = 360 m/s
The muzzle speed of the bullet = 360 m/s