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Pushoam
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Homework Statement
Homework Equations
The Attempt at a Solution
Every small part of the trajectory can be taken as a circular arc.
Then,
$$\frac { m v^2} R ≤ kmg $$
But how to find out R from the sine-curve?
Please give me a reference for this information .Hiero said:In general (for not simply circular motion) the radius of curvature (the R in your centripetal acceleration formula) is given by (one over) the magnitude of acceleration of a particle moving along the curve at the point with (always) unit speed.
I think you dropped a factor a/α in the differentiation.Pushoam said:Is this correct so far?
Sorry I think that wasn't the simplest way to put it, but @haruspex's link is worth looking at; it is what I had in mind in my first reply.Pushoam said:Please give me a reference for this information .
Yes.Pushoam said:So, the maximum allowed speed is ##v_{mx} = \sqrt { k g R_{mn} }##
where Rmn is the minimum radius of curvature
OKIf the curve is given in Cartesian coordinates as y(x), then the radius of curvature is (assuming the curve is differentiable up to order 2):
##R = | \frac { \left ( 1 + y' ^2\right )^ \frac 3 2 } { y" }|##
Yes. It's not hard to prove it without a computer. If you inspect the expression for R as a function of x for this specific y(x), you can see that the denominator attains its maximum value at the same point that the numerator attains its minimum value.Rmn, turns out to be radius of curvature at that point where Sine function has maximum value.
I'm not sure what you are saying here. What curve are you referring to?So, the curve is a straight line.
Why wouldn't a slope of 1 also imply that the curve is a straight line?Pushoam said:Slope being zero implies that the curve is a straight line.
TSny said:Why wouldn't a slope of 1 also imply that the curve is a straight line?
Knowing the value of the slope of a curve at some point does not tell you anything about the curvature at that point. Rotating the whole curve rigidly would change the slope values but would not change the curvature values.
Yes, the slope is zero, but that is just y'. Your straight line there is just the tangent. Putting y'=0 in your formula does not give infinity. You need to calculate y" and plug that in too. (If that were zero then it would be a straight line.)Pushoam said:What I want to say that even the upper part of a circle has maximum at some point say(x0 , y0 ). And if I use the above formula for calculating the Radius of curvature , then around (x0 , y0 ), the curve is a straight line with slope zero and a straight line has an infinite radius of curvature. I am having some confusion here.
What is a lateral acceleration and how to relate it with the problem?Nidum said:Do you actually need to find the radius of curvature ?
Can this problem be solved more elegantly by considering the lateral acceleration of the car directly ?
Pushoam said:I copied these latex codes from mathematica. Now how to bring it in the standard form?
Do you mean ##\ddot y##? The constant speed condition makes that a bit tricky.Nidum said:Can this problem be solved more elegantly by considering the lateral acceleration of the car directly ?
A sine curve trajectory is a path or motion that follows the shape of a sine curve. It is a smooth, repetitive curve that is often seen in nature and can be described by the mathematical function y = sin(x).
Some real-life examples of objects following a sine curve trajectory include a pendulum swinging back and forth, a metronome ticking, a bouncing ball, and the motion of a swinging door.
The shape of a sine curve trajectory is affected by the amplitude, frequency, and phase of the curve. The amplitude determines the height of the curve, the frequency determines how often the curve repeats, and the phase determines where the curve begins on the x-axis.
Sine curves and simple harmonic motion are closely related. Simple harmonic motion is a type of motion described by a sine curve, where the restoring force is directly proportional to the displacement from equilibrium. This means that objects moving in simple harmonic motion will follow a sine curve trajectory.
Sine curve trajectories are used in many areas of science and engineering, such as in the study of oscillations and vibrations, in electrical circuits and signals, and in the design of structures and machines. They can also be used to model natural phenomena such as sound waves and ocean waves.