Does the Bead's Speed Change as It Slides Along a Frictionless Curve?

AI Thread Summary
The discussion revolves around a bead sliding along a frictionless curve in a vertical plane, starting from rest. The participant evaluates six statements regarding the bead's acceleration and speed at various points, concluding that points C and A have equal potential energy, thus equal kinetic energy, while noting the difference in velocity due to direction. They assert that the acceleration in the x-direction at the lowest point (H) is zero and that the acceleration in the y-direction is increasing as the bead descends. The participant expresses uncertainty about their reasoning and seeks validation for their answers. The discussion highlights the importance of understanding energy conservation and the effects of gravitational acceleration on the bead's motion.
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Homework Statement


The figure below shows a bead sliding without friction along a curved wire in a vertical plane.
IMAGE: http://img545.imageshack.us/i/bead.png/

The bead slides starting from rest at position B on the frictionless wire. The direction of the gravitational field is in the -y direction (toward the bottom of the page).

I then have 6 statements that I have to determine if they are true, false, greater than, less than, or equal to:

1.) The acceleration in the x-direction at H is ... zero.
2.) The speed at C is ... the speed at A.
3.) The acceleration in the y-direction at H is ... zero.
4.) The acceleration at C is zero.
5.) The velocity at A equals the velocity at C.
6.) The speed at H is ... the speed at C.

Homework Equations


change KE + change PE = 0


The Attempt at a Solution


I feel confident for numbers 2, 5, and 6.

2 - Points C and A appear to be at the same height which means their PE is the same which means their KE are the same. Equal To

5 - While the speeds may be the same (for the same reason as 2) the velocity also takes into account the direction, which isn't the same in this case. False

6 - H is lower than C, which means there is a greater amount of potential energy at C. Greater Than

Now for 1, 3, and 4.

1 - It appears to be at the bottom of the curve. As the bead is descending the bead is gaining speed in the x direction, and as the the bead is ascending the bead is losing speed. It has to change signs at some point which means it has to equal zero at the bottom. Equal To

3 - The speed increases rapidly as the bead first falls and then tapers off until the speed downwards is zero. The acceleration must be towards the positive Y direction then? Greater Than

4 - In this case both accelerations (X and Y directions) must be taken into account. I believe the acceleration in the X direction is still zero because of the same line of reasoning as 1. Acceleration in the -Y direction should actually be increasing though. False

Is there anything wrong with my way of thinking? I just don't feel overly confident in my answers.

Thanks a bunch!
 
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panx said:
The diagram is missing. :( or else I would have tried.
If you want somebody to explain it on a white-board, you can take live online help offered by www.myphysicsbuddy.ca[/URL]. I used the free demo given and they are good at such stuffs.
Let me know if it helps.
Cheers[/QUOTE]
The picture doesn't show up?

[ATTACH=full]140319[/ATTACH]
 

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Well I added the link to the picture. Hope that works. Thanks for your offer, but I'm too cheap to pay for help :P (I can see I get one free trial)
 
Figured it out :approve:
 
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