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# A body of mass $2kg$ is at rest. What should be the magnitude of force which will make the body move with a speed of $30m/s$ at the end of $1s$?

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## Step1: Given dataThe mass of the body is $2kg$.The body was at rest, $initialvelocity,u=0m/s$ The body moves with a speed of $30m/s$ at the end of $1s$ i.e., $finalvelocity\left(v\right)=30m/sandtime\left(t\right)=1sec$Step2: Formula usedAccording to Newton’s second law of motion, the magnitude of the applied force on a body is equal to the product of its mass and acceleration.$F=m×a\left[whereF=force,m=mass,a=acceleration\right]$Step3: Calculating forceWe say that a body accelerates when an imbalanced force is applied to it. The rate of change in velocity of a body with respect to time is known as acceleration.$a=\frac{\left(v-u\right)}{t}\left[wherea=acceleration,v=finalvelocity,u=intialvelocity,t=1sec\right]\phantom{\rule{0ex}{0ex}}a=\frac{\left(30-0\right)}{1}\phantom{\rule{0ex}{0ex}}a=30m/{s}^{2}$Therefore $a=30m/{s}^{2}$Substituting the value of mass and acceleration in the formula$F=m×a\phantom{\rule{0ex}{0ex}}F=2×30\phantom{\rule{0ex}{0ex}}F=60N$Hence, the magnitude of the force that will make the body move is $60N$.  Suggest Corrections  4      Similar questions  Explore more