Let's first find the final velocity of the car:
v=v0+at=0+2 s2m⋅10 s=20 sm.Then, we can find the distance traveled by the car:
d=21(v+v0)t=21⋅(20 sm+0)⋅10 s=100 m.Let's also find the net force acting on the car:
Fnet=ma=1500 kg⋅2 s2m=3000 N.Then, we can find the net work done by the force:
Wnet=Fd=3000 N⋅100 m=3⋅105 J.Let's find the force of friction acting on the car:
Ffr=μmg=0.02⋅1500 kg⋅9.8 s2m=294 N.Then, we can find the work done by the force of friction:
Wfr=Ffrdcosθ=294 N⋅100 m⋅cos180∘=−29400 N.Finally, we can find the work done by the car engine during start-up:
Wnet=Weng+Wfr,Weng=Wnet−Wfr=3⋅105 J−(−29400 N)=3.294⋅105 J.
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