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If a car generates 18hp (which is 13428Watts) when traveling at a steady speed of 88km/h (which is 24.44m/s), what must be the average force exerted on the car due to friction and air resistance?

User Artoon
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2 Answers

2 votes

Answer:

Step-by-step explanation:

549N

parameters given

power generated by car, P = 18hp =13428W

steady speed , S = 24.44m/s

force, F = ?

For a car that is moving with steady speed (constant). Power the car generates is what it used to overcome force of friction. so

P = F X S

making P the subject of the formula

F = P/S

using the SI unit

= 13428/24.44

F = 549N

User Xh Lin
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7.5k points
1 vote
Power = Force * Velocity

First convert to SI units:
88 km/h = 24.44 m/s
18 Hp = 13,428 Watts

Force = P/V = 549 newtons
User Bureaucoconut
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