Physics turns and centripetal force on flat roads

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Discussion Overview

The discussion revolves around the concept of centripetal force and friction in the context of a car navigating turns on flat roads. Participants explore the nature of the frictional force that acts towards the center of the circular path during such motion, questioning its origin and implications.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about the frictional force that points towards the center of the circle, questioning what causes this force when the road is flat and the car is moving straight.
  • Another participant argues that without a force directed towards the center, the car would not be able to maintain its circular path, drawing a parallel to a rubber stopper being spun by a string.
  • A different viewpoint suggests that if there is a tendency for the car to slip outward, this will result in a frictional force directed towards the center of the circle.
  • One participant highlights the behavior of objects inside the car during a hard turn, noting that they roll towards the sides due to their inertia, which implies a lack of force acting on them towards the center.
  • Another participant explains that a car can only navigate a circle when its front wheels are turned towards the center, with friction opposing the sideways motion of the tires, facilitating the turn.
  • A participant reiterates their confusion about the origin of the frictional force, acknowledging its connection to the road and tires but struggling to pinpoint its exact cause.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and confusion regarding the nature of the frictional force in circular motion. While some provide explanations and analogies, there is no consensus on the precise origin of the force or how it operates in this context.

Contextual Notes

Participants mention the role of tire orientation and the effects of inertia, but there are unresolved questions about the specific mechanisms behind the frictional force and its relationship to the car's motion.

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I am confused about this. I learned that the frictional force is pointing towards the center of the circle in circular motion (on a flat road) due to the tires.

The thing is, I don't understand what the result of this friction is.

The road is flat, and the motion of the car is straight. Therefore, the only friction that I can think of would be one opposite to the cars motion. What is causing the friction which has a direction pointing to the center of the circular path the car is traveling in?

Can someone break it down for me? I just can't seem to think about what could be causing this frictional force which is pushing the car to the center of the circle.
 
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If you don't have a force pointing toward the center of the circle what is keeping the car from flying off the side of the road? Its the same as a string on a rubber stopper spinning, if not for the string the stopper would not go in a circle.
 
If there is a tendency for the car to slip outwards, then there will be a frictional force towards the centre of the circle.
 
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Also think about taking a hard turn in your car, which way does all the stuff in your floor board/back seat roll?
 
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Under normal conditions, a car goes in a circle only when its front wheels are turned toward the center of the circle. Because they are turned, they are somewhat sideways to the direction of its instantaneous velocity. Friction opposes their sideways motion, and causes the car to go round.
 
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Jesse H. said:
Also think about taking a hard turn in your car, which way does all the stuff in your floor board/back seat roll?

It would hit the sides because it still wants to continue its straight motion, there is no force causing the objects to accelerate to the center of the circle.

I understand that there is a force, but I am just confused as to what the force is a result of.

I am unsure of exactly what is causing this frictional force. I know it has something to do with the road and the tires, but I just can't exactly pin point it.

voko said:
Under normal conditions, a car goes in a circle only when its front wheels are turned toward the center of the circle. Because they are turned, they are somewhat sideways to the direction of its instantaneous velocity. Friction opposes their sideways motion, and causes the car to go round.

Thank you. That is exactly what I was looking for.

Also, thank you for everyone else too. I appreciate your time
 

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