A bullet is fired from a gun. The force on

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A bullet is fired from a gun. The force on the bullet is given by $F = 600 - 2 \times {10^5}t$, where $F$ is in newtons and $t$ in seconds. The force on the bullet becomes zero as soon as it leaves the barrel. What is the average impulse imparted to the bullet  ........... $N-s$

A

$9$

B

$0$

C

$0.9$

D

$1.8$

A bullet is fired from a gun. The force on the bullet is given by $F = 600 - 2 \times {10^5}t$, where $F$ is in newtons and $t$ in seconds. The force on the bullet becomes zero as soon as it leaves the barrel. What is the average impulse imparted to the bullet  ........... $N-s$

$F = 600 - 2 \times {10^5}t = 0$

$⇒$ $t = 3 \times {10^{ - 3}}\,\sec $

Impulse $I = \int_0^t {F\,dt} = \int_0^{3 \times {{10}^{ - 3}}} {(600 - 2 \times {{10}^3}t)dt} $ $ = [600t - {10^5}{t^2}]_0^{3 \times {{10}^{ - 3}}} = 0.9\,N  \sec $