• Support PF! Buy your school textbooks, materials and every day products Here!

Particle on a circle

  • Thread starter faen
  • Start date
  • #1
140
0

Homework Statement


Untitled-1_zps6e2550ce.png



Homework Equations



I suppose newtons third and second law.

centripetal acceleration = v^2 /R

The Attempt at a Solution



I'm thinking that the force due to weight, should be exceeded by the centripetal acceleration?

I couldn't get the calculations to add up though. Anyone know how to solve it or if I'm on the right track at all? Thanks for any help! :)
 

Answers and Replies

  • #2
ehild
Homework Helper
15,492
1,874
What forces act on the particle when sliding on the big sphere, and in what directions?

ehild
 
  • #3
140
0
The weight acts perpendicular to the circle, and movement acts parallel to the circle.
 
  • #4
747
36
I think you are on the right track. "I'm thinking that the force due to weight, should be exceeded by the centripetal acceleration?"
Consider the forces acting normal to the surface of the sphere where the particle leaves the sphere.
 
  • #5
haruspex
Science Advisor
Homework Helper
Insights Author
Gold Member
33,495
5,425
The weight acts perpendicular to the circle, and movement acts parallel to the circle.
No, weight is due to gravity, so always acts vertically, and movement is not a force.
There is a force perpendicular to the arc of the circle. What is it usually called and where does it come from?
You need a variable to denote the particle's position at an arbitrary point. You could use the height it has descended so far, but the angle of arc it has travelled will be more convenient. What will be its speed when at angle theta? What will be its acceleration if it is remaining in contact with the circle?
 

Related Threads on Particle on a circle

  • Last Post
Replies
1
Views
906
  • Last Post
2
Replies
34
Views
1K
  • Last Post
Replies
10
Views
1K
Replies
2
Views
2K
Replies
3
Views
1K
Replies
1
Views
4K
Replies
3
Views
625
Replies
7
Views
1K
Replies
2
Views
755
Top