A 40kW car runs at a speed of 0.5m/s on a straight road The resistance to the car 2. Work done by the car after 1.5h

1. Because it is moving in a straight line at a constant speed, the two forces are balanced, and the resistance is equal to the traction
f=F=P/v=40000W/0.5m/s=80000N
2、t=1.5h=5400s
W＝Pt-=40000Wx5400s=216000000J

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