Banked Curve Impossible Problem

AI Thread Summary
The discussion revolves around calculating the range of speeds a car can safely navigate a banked curve with a radius of 67 m, designed for a speed of 95 km/h, and a static friction coefficient of 0.30. Participants express confusion about how to approach the problem, particularly regarding the necessary banking angle and the forces involved. It is noted that the horizontal component of the normal force and static friction are crucial for maintaining centripetal acceleration. Some contributors suggest that the problem may be flawed due to missing information, while others point out that the banking angle can be derived from the given design speed. Ultimately, the conversation highlights the complexities of solving physics problems involving banked curves.
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Homework Statement


A curve of radius 67 m is banked for a design speed of 95 km/h. If the coefficient of
static friction is 0.30 (wet pavement), at what range of speeds can a car safely handle the
curve?


Homework Equations


2ngvr4m.png

I drew this freebody diagram.


The Attempt at a Solution


I have no clue how to do this.

Anyways, on the range of speeds there is a minimum speed and a maximum speed.

For the minimum speed friction has act enough that the car doesn't slip off the hill? I think, again I have no ****ing clue.

For the maximum speed friction has to be enough so the car doesn't fly off the curve. I think


Anyways we probably have to solve for some angle, but I have no clue where or how this happens.

Fnet is not existent here?


anyways, All I have done is convert 95kmh to m/s which is 26.388m/s.

SO nobody knows how to solve this question? It is ranked as one of the world's hardest problems.
 
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I think you're over exaggerating the problem a bit.

Inclined edges add a force that keeps the car on its proper path as it circles a banked turn. This force is the horizontal component of the car’s normal force. It along with the static force of friction create the force required for centripetal acceleration and ensures the car does not fly off the ramp.

This article will be helpful to you: http://en.wikipedia.org/wiki/Banked_turn
 
Zondrina said:
I think you're over exaggerating the problem a bit.

Inclined edges add a force that keeps the car on its proper path as it circles a banked turn. This force is the horizontal component of the car’s normal force. It along with the static force of friction create the force required for centripetal acceleration and ensures the car does not fly off the ramp.

This article will be helpful to you: http://en.wikipedia.org/wiki/Banked_turn

Yea all those equations don't make no sense if you don't have the angle. Which they forgot to tell me in the question
 
physicsnobrain said:
Yea all those equations don't make no sense if you don't have the angle. Which they forgot to tell me in the question

Indeed, the question is flawed.
 
Zondrina said:
Indeed, the question is flawed.

unfortunately I still have to solve it so I don't get a zero. Thanks for the help anyways.
 
physicsnobrain said:
A curve of radius 67 m is banked for a design speed of 95 km/h. If the coefficient of
static friction is 0.30 (wet pavement), at what range of speeds can a car safely handle the
curve?

You can find the banking angle from the first sentence of the problem. It means that the cars ravelling with 95 km/h can do the curve even with zero friction. What is the angle then??


ehild
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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