Question

A body is acted on by a force given by $F=(10+2t)$ N . The impulse received by the body during the first four seconds is :

• A. $40Ns$
• B. $56Ns$
• C. $72Ns$
• D. $32Ns$

Answer 1

The correct option is B $56Ns$

Given force, $F=(10+2t)N$

Impulse, $J={\int }_0^{4}F\cdot dt$

$={\int }_0^4(10+2t)\cdot dt={[10t+t^2]}_0^4=\left[10\right(4)+4^2]=56Ns$.