Calculating Resistance Force of a Car Driven at 76km/h with 48 kW Engine Power

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To calculate the average resisting force of a car traveling at 76 km/h with a 48 kW engine, the relationship between power, force, and velocity is crucial. Power is defined as the product of force and velocity, which means that the resisting force can be derived from the equation: Power = Force x Velocity. Since the car maintains a constant speed, the net force acting on it is zero, indicating that the resisting force equals the force exerted by the engine, but in the opposite direction. Thus, the total engine power is entirely used to overcome frictional forces. This understanding confirms that at constant speed, the engine's power directly correlates with the resisting forces acting on the vehicle.
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a car is driven at a constant speed of 76km/h down a road. The car's engine delivers 48 kW of power. Calculate the average force that is resisting the motion of the car

any help would be appreciated. I had an idea, but i don't know if its right.
 
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What is the relationship between Power, force and velocity ?
 
well i was thinking power=w/t, so power=fd/t, d/t is velocity, so power = force x velocity, and i figure out that force. it is asking for resisting force, so it is asking for the frictional force. Since it is constant speed, the net force is zero, so it would just be the negative force of the above force. This is what i was thinking
 
Well, there you go. :smile:

Another way to look at it would be that all the engine's power is going to overcome friction. This is why the car is not accelerating.
 
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thats right?
 
Yup yup!


Hmm, 'yup yup!' is too short, so I had to add this bit.
 
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