Question

Calculate the power of an engine which can maintain the a speed of $50m/sec$, for a train of mass $3\times {10}^6$kg on a rough level track. The co-efficient of friction is $0.05$. Given $g=10m/se{c}^2.$

Answer 1

Given, $Speed=50m/s,Mass=3\times {10}^{6}kg$

$Coefficient=0.05,g=10m/s^2$

So, the frictional force act on it $\mu N$ Where, $N=mg$

$F=\mu mg=0.05\times 10\times 3\times {10}^6=15\times {10}^{5}N$

Thus the power delivered by thee train $F\times v=15\times {10}^{5}N\times 50$

$=75\times {10}^{6}J/s$