How Do You Calculate the Force of Friction for a Moving Car?

AI Thread Summary
To calculate the force of friction for a moving car, it is essential to recognize that when the car travels at a constant velocity, the net force acting on it is zero. In this scenario, a 2000 kg car moving at 30 m/s has a forward force of 4000 N from the motor, which is entirely countered by the force of friction. Therefore, the force of friction must also be 4000 N to maintain this constant speed. Since there is no acceleration, the forces are balanced, confirming that the frictional force equals the applied force. Understanding these principles is crucial for accurately calculating friction in similar scenarios.
Koyuki
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This is probably horribly easy, but it's almost 1 AM so I'm going nutty trying to figure this one out.

The questoni: "A 2000kg car is traveling at a constant 30m/s with the motor producing a force of 4000 N forward. Find the force of friction."

I drew the diagram. Is acceleration 0?

I'd appreciate any help. Thank you~
 
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There is a force forward of 4000N that is being completely negated by friction, since it is moving at constant velocity.. If the net force is 0, what is the force of friction?
 
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