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3 years ago

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When an automobile moves with constant speed down a highway, most of the power developed by the engine is used to compensate for

the mechanical energy loss due to frictional forces exerted on the car by the air and the road. If the power developed by the engine is 196 hp, estimate the total friction force acting on the car when it is moving at a speed of 32 m/s. One horsepower equals 746 W.

1 answer:

sveta [45]3 years ago

7 0

Answer:

F = -4567.40 N

Explanation:

Given that,

The power developed by the engine, P = 196 hp

1 hp = 746 W

196 hp = 146157 W

Speed of the car, v = 32 m/s

Let F is the total friction force acting on the car. The product of force and velocity is called the power developed by the engine. It is given by :

$P=-F\times v$

$F=\dfrac{-P}{v}$

$F=\dfrac{-146157\ W}{32\ m/s}$

F = -4567.40 N

So, the total frictional force acting on the car is 4567.40 N. Hence, this is the required solution.

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