From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 m/s. Calculate the initial recoil velocity of the rifle.
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Answers
Answer:
thats the answer
Explanation:
Initially, the rifle is at rest.
Thus, its initial velocity (v) = 0
The total initial momentum of the rifle and bullet system
⇒ (m1+m2) × v = 0
The total momentum of the rifle and bullet system after firing
= m1v1 + m2v2
= (4 × v1 ) + (0.05 × 35)
= 4v1 + 1.75
According to the law of conservation of momentum
Total momentum after the firing = Total momentum before the firing
4v1 + 1.75 = 0
v1= -1.75 / 4
v1 = – 0.4375 m/s
The negative sign indicates that the rifle recoils backwards with a velocity of 0.4375 m/s.
From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 m s-1. Calculate the initial recoil velocity of the rifle.
Answer
Mass of the rifle, m1 = 4 kg
Mass of the bullet, m2 = 50g = 0.05 kg
Recoil velocity of the rifle = v1
Bullet is fired with an initial velocity, v2 = 35 m/s
Total mass = m1 + m2 = 4 + 0.05 = 4.05 kg
Since the system was at rest , velocity (v) = 0
Momentum ( before firing ) = mass x velocity = ( m1 + m2 )v = ( 4.05 ) 0 = 0 kg m/s
Total momentum = momentum of bullet + momentum of rifle = m1 v1 + m2 v2
= 0.05 x 35 + 4 x v2 = 7/4 + 4 v2
Since the total momentum remain conserved
Total momentum before firing = Total momentum after firing
0 = 7/4 + 4 v2
4 v2 = - 7/4
v2 = - 7/16
v2 = -04375 m/s
Thus , the recoil velocity of the pistol is -0.4375 m/s .
The negative sign of velocity means that the rifle will recoil in the opposite direction of the bullet