From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an ini

1.	From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 ms-1. Calculate the initial recoil velocity of the rifle.
Answer» Mass of rifle m₁ = 4 kg Mass of bullet m₂ = 50 g = \(\frac{50}{1000}\) = 0.05 kg Initial velocity of rifle u₁ = 0 Initial velocity of bullet u₂ = 0 Final velocity of rifle (recoil velocity) v₁ = v Final velocity of bullet v₂ = 35 ms^-1 According to law of conservation of momentum m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂. 4(0) + 0.05 (0) = 4v + 0.05 × 35 4v = – 1.75 v = – 0.44 m/s

From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 ms-1. Calculate the initial recoil velocity of the rifle.

Answer»

Mass of rifle m₁ = 4 kg

Mass of bullet m₂ = 50 g = \(\frac{50}{1000}\) = 0.05 kg

Initial velocity of rifle u₁ = 0

Initial velocity of bullet u₂ = 0

Final velocity of rifle (recoil velocity) v₁ = v

Final velocity of bullet v₂ = 35 ms^-1

According to law of conservation of momentum

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂.

4(0) + 0.05 (0) = 4v + 0.05 × 35

4v = – 1.75

v = – 0.44 m/s