Question

- a bullet of mass 10gm is fired with a velocity of 40 m/s from a gun of mass 8 kg. find the recoil velocity (in m/s) of the gun.

Answer 1

Hey !!!!

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According To The Question,

M1 = 10/1000 kg = 1/100 kg
M2 = 8 kg

U1 =0 m/s ( Both Start From Rest )
U2=0 m/s

V1 = 40 m/s
V2 = V2 m/s

We Know That,

Total Momentum Before and after are same

M1U1 + M2U2 = M1V1 + M2V2

1/100×0 + 8×0 = 1/100×40 + 8×V2

0 = 4/10 + 8V2

0 = 4/10 +8V2/1

0 = 4+80V2/10

0 = 4 + 80 V2 ( Transposing, 10 to LHS)

-4 = 80 V2

-4/80 = V2

-1/20 = V2

-1/5 m/s = V2

-0.2 m/s = V2

Here, '-' sign Indicates that, gun recoils from right to left

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Hope This Helps......!!!!

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