Question

A bullet of mass 10g is fired horizontally with a velocity of 240m/s from a pistol of mass 1.2kg.What is the recoil velocity of the pistol?​

Answer 1

Answer :

Mass of bullet = 10g = 0.01kg

Mass of pistol = 1.2kg

Velocity of bullet = 240m/s

We have to find recoil velocity of gun$.$

Here, No net force acts on the whole system so we can apply concept of momentum conservation.

Initial momentum of whole system will be zero (i.e., at rest)

As per law of momentum conservation, initial momentum of system will be equal to the final momentum of system.

Let's calculate ☃

➝ P_initial = P_final

➝ 0 = MV + mv

➝ V = -mv/M

➝ V = -(0.01×240)/1.2

➝ V = -2m/s

[፨ Negative sign shows opposite direction.]

Answer 2

$\small\underline{\overline{\mid{\bold{\orange{GIVEN-}}\mid}}}$

Bullet=>

Mass= 10g

Velocity= 240m/s

Pistol=>

Mass=1.2kg = 1200g

$\small\underline{\overline{\mid{\bold{\red{FIND-}}\mid}}}$

recoil velocity of the pistol-?

$\small\underline{\overline{\mid{\bold{\blue{FORMULA-}}\mid}}}$

Conservation of Momentum

$\boxed {M_1 V_1 = M_2 V_2}$

$\small\underline{\overline{\mid{\bold{\green{SOLUTION-}}\mid}}}$

putting all given values in formula we get,

$10 \times 240 = 1200 \times V_2$

$\dfrac{2400}{1200} = V_2$

$V_2= 2m/s$

Hence,recoil velocity of the pistol is 2m/s.