Answer:
bullet = 450 J
rifle = 1.3 J
So, the kinetic energy of bullet is much more than the kinetic energy of gun.
Explanation:
mass of rifle, mR = 3.50 kg
mass of bullet, mB = 10 g
velocity of bullet, vBx = 300 m/s
Let VG is the recoil velocity of gun.
By using the conservation of momentum
mass of gun x recoil velocity of gun = mass of bullet x velocity of bullet
3.50 x V = 0.01 x 300
V = 0.86 m/s
kinetic energy of bullet, KB = 0.5 x mB x vB²
KB = 0.5 x 0.01 x 300 x 300 = 450 J
kinetic energy of rifle, KG = 0.5 x mG x v²
KG = 0.5 x 3.5 x 0.86 x 0.86 = 1.3 J
So, the kinetic energy of bullet is much more than the kinetic energy of rifle.