Question

A car needs to generate 75.0 hp in order to maintain a constant velocity of 18.2 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.)

Answer 1

Answer:

The magnitude of the force is F= 3072.9 N.

Explanation:

The expression for the power in terms of force and velocity is as follows;

P=Fv

Here, P is the power, F is the force and v is the velocity.

Rearrange the above expression to get the value of the force.

$F=\frac{P}{v}$

Convert power from horsepower to watt.

P=75.0 hp

P= (75)(745.7) W

P= 55,927.5 W

Put P= 55,927.5 W and v= 18.2 meter per second in the above expression.

$F=\frac{55,927.5}{18.2}$

F= 3072.9 N

Therefore, the magnitude of the force is F= 3072.9 N.