A car needs to generate 75.0 hp in order to maintain a constant velocity of 27.3 m/s on a flat road. What is the magnitude of the total resistive force acting on the car (due to friction, air resistance, etc.)? (1 hp = 746 W) A) 2.05 × 10³ N B) 2.75 N C) 1.03 × 10³ N D) 2.87 × 10³ N

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Quizplus · Accepted Answer

The power needed to overcome the resistive force is equal to the power generated by the car. Therefore, the magnitude of the total resistive force is:$$P = Fv$$$$F = \frac{P}{v} = \frac{75.0 	ext{ hp} 	imes 746 	ext{ W/hp}}{27.3 	ext{ m/s}} = 2.05 	imes 10^3 	ext{ N}$$

A Car Needs to Generate 75