Confusion with the example of Newton’s first law

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Discussion Overview

The discussion revolves around the effects of abrupt turns in a vehicle, specifically examining why a driver may not feel as much lateral force as a passenger during a sharp turn, in the context of Newton's first law of motion. The scope includes conceptual reasoning and technical explanations related to forces experienced in a moving vehicle.

Discussion Character

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

Main Points Raised

  • One participant suggests that the driver may not feel as much swerve because they are prepared for the turn and can hold onto the steering wheel tightly.
  • Another participant argues that both the driver and passenger experience forces due to the abrupt turn, but the driver might be fighting against the force more effectively.
  • A different perspective is presented that considers the dynamics of the vehicle's tires and the concept of centrifugal force, suggesting that the driver experiences greater centrifugal force due to the differing velocities of the tires during a turn.
  • Some participants propose simplifying the scenario to a trolley with tins of beans to illustrate the forces at play, arguing that the same principles apply regardless of the vehicle type.
  • There is a discussion about the role of frictional forces and how they relate to the forces experienced by passengers in the vehicle during a turn.
  • One participant expresses skepticism about the complexity of the explanations, suggesting that the example may not accurately represent the forces involved.
  • Another participant emphasizes that the forces experienced by the tins in a simplified scenario would depend on factors such as friction and distance from the center of curvature.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the reasons behind the differing experiences of the driver and passenger during a turn. Multiple competing views and interpretations of the forces involved remain present throughout the discussion.

Contextual Notes

Participants express varying levels of understanding and clarity regarding the physics involved, with some suggesting that the complexity of the explanations may obscure the fundamental concepts. There are also references to specific conditions, such as speed and friction, that may affect the outcomes discussed.

steevan78
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Consider a case where 2 people are in a car driving in a straight line at sufficient speed. At some point the driver takes an abrupt 90 degree right turn and owing to reasons attributed to Newton’s first law the co-passenger swerves into the driver (i.e. to the left).

My question is why doesn’t the driver feel as much swerve as felt by the co-passengers to the left (towards his door)? Is that because he is firmly holding the wheel? Or is it that I am not a keen observer?

Thanks in advance for any convincing answers.
 
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Most probably that the driver was ready for the abrupt turn, for which he could hold on very tight to the wheel. Otherwise, he would be pushed against the door.

The same would have happened to the passenger. If the passenger could get ready by holding to the holly crap bar, the virtual force could be counter act.

Cheers
 
the driver does he is just fighting it you still feel the force of you wanting to go on in a straight line the fule in tank would be doing the same as well
 
My question is why doesn’t the driver feel as much swerve as felt by the co-passengers to the left (towards his door)?

Why do you thing he does not?
 
steevan78 said:
Consider a case where 2 people are in a car driving in a straight line at sufficient speed. At some point the driver takes an abrupt 90 degree right turn and owing to reasons attributed to Newton’s first law the co-passenger swerves into the driver (i.e. to the left).

My question is why doesn’t the driver feel as much swerve as felt by the co-passengers to the left (towards his door)? Is that because he is firmly holding the wheel? Or is it that I am not a keen observer?

Thanks in advance for any convincing answers.
No, the driver on the left must swerve more during a right turn because at this point, the right of rear and front tyres have lesser velocity than the left, so by F=mv^2/r, he experiences greater centrifugal force.
Or maybe both experience the same force as r is also lesser for the right tyres.
You cannot turn your car abruptly by 90 degrees, can you?
The angular velocity of all the tyres during a curve is the same, so by equation
F=mr*(omega)^2, the driver as wall as the one sitting behind him to the left experience more force.
 
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vin300 said:
No, the driver on the left must swerve more during a right turn because at this point, the right of rear and front tyres have lesser velocity than the left, so by F=mv^2/r, he experiences greater centrifugal force.
Or maybe both experience the same force as r is also lesser for the right tyres.
You cannot turn your car abruptly by 90 degrees, can you?
The angular velocity of all the tyres during a curve is the same, so by equation
F=mr*(omega)^2, the driver as wall as the one sitting behind him to the left experience more force.

i think ur looking at it all wrong way (im just a fool who can't spell so take what i say with a pinch of salt) but tyres are nothing to do with it all,to be honest the car has nothing to do with it,if u made the idear simple as you can for simple people like me :) if it was a trolly with 2 tins of beans and you did the experiment my simple head says the 2 tins will carry on forward at equal force
but like i say what do i know
 
kevinfr0st said:
i think ur looking at it all wrong way (im just a fool who can't spell so take what i say with a pinch of salt) but tyres are nothing to do with it all,to be honest the car has nothing to do with it,if u made the idear simple as you can for simple people like me :) if it was a trolly with 2 tins of beans and you did the experiment my simple head says the 2 tins will carry on forward at equal force
but like i say what do i know
When the trolley curves, it goes on changing direction at every point on the curve.The trolley has the same speed, but different velocity(velocity is a vector)at every point on the curve.
To produce a constant change in velocity there must be a constant acceleration(constant force) which if you want to understand, by Newton's thid law is exactly equal and opposite to the force experienced by the person in the car causing swerving.
Where does this opposite force come from?
It is the frictional force between the tyres of the vehicle and the road, which is always equal in magnitude to the force a person in the car experiences. It is directed to the centre of the curvature so you are pushed radially outward.
Next, you can read the last two lines of my previous reply.
 
vin300 said:
When the trolley curves, it goes on changing direction at every point on the curve.The trolley has the same speed, but different velocity(velocity is a vector)at every point on the curve.
To produce a constant change in velocity there must be a constant acceleration(constant force) which if you want to understand, by Newton's thid law is exactly equal and opposite to the force experienced by the person in the car causing swerving.
Where does this opposite force come from?
It is the frictional force between the tyres of the vehicle and the road, which is always equal in magnitude to the force a person in the car experiences. It is directed to the centre of the curvature so you are pushed radially outward.
Next, you can read the last two lines of my previous reply.

i still think ur adding more into it then ur supposed to the question, isn't possable,it is a example,the car and 2 passengers were used to get it into visual contex,if there was a speed put into it all ect then it would be about the car ie if to fast the car will spin,even with the trollys and tins of beans it don't totally give true example because the weight of beans and friction contact with trolly may pull the beans off corse a bit and might even spin the tins,lol was just thinking of the old war machens that had A frame and counter weight on long rotating arm the arm and weight only goes in a round motion but the object gets thrown forward isn't that the same but in reverse,
this is only my thoughts on the matter and take it with a pinch of salt
 
kevinfr0st said:
i still think ur adding more into it then ur supposed to the question, isn't possable,it is a example,the car and 2 passengers were used to get it into visual contex,if there was a speed put into it all ect then it would be about the car ie if to fast the car will spin,even with the trollys and tins of beans it don't totally give true example because the weight of beans and friction contact with trolly may pull the beans off corse a bit and might even spin the tins,lol was just thinking of the old war machens that had A frame and counter weight on long rotating arm the arm and weight only goes in a round motion but the object gets thrown forward isn't that the same but in reverse,
this is only my thoughts on the matter and take it with a pinch of salt
What you have written is difficult to read and understand.
I think that I have mentioned everything i should've.
Yes the tins may rotate outwards on the top and the reason for this is that friction pulls it inside at the bottom and the same centrifugal force results in highest torque on the top(outward) and the tin is thrown away, but this happens only when its velocity is greater than the value sqrrt{(mu)*r*g} where mu is the coefficient of friction between the tin and the trolley, r is its distance from the centre of curvature, so the tin on the left during a right turn is thrown away more easily as it experiences greater force.
 
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