Question

A car of mass 500kg working against the resistance of 500N accelerates from rest to 20m/s in 100M. Calculate the amount of work done.

Answer 1

Given $t=100mins=6000sec$

$v-u=at$

$20=a\times 6000$

$a=\frac{20}{6000}=0.00334m/s^2$

$F-500=ma$

$F=500+500\times 0.00334+1.66$

$=501.66N$

Work done $=F\times$displacemnt in 100mins

$=501.66\times \left(\frac{1}{2}a{t}^2\right)$

$=501.66\times (\frac{1}{2}\times 0.00334\times (6000{)}^2$

$=30096J$