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

Gravitational field owing to a uniform circular plate

  • #1

Homework Statement



Show that the gravitational field due to thin uniform circular plate of radius a at point distant R from center and on the axis passing through the center and perpendicular to the plane of the plate is given by E= -2πGρ[1-R/(a^2+R^2)^1/2]

Homework Equations



F= GMm/r^2
E=F/m

The Attempt at a Solution


I really don't have any proper approach as to how I should go about this problem. How am I going to get a negative sign in the field created by the plate making sure the field is on the vertical axis passing through the center??? Would be very helpful if any of you could drop a hint as to how I should start this problem as I am at a total loss with this one.
 

Answers and Replies

  • #2
Nathanael
Homework Helper
1,650
239
I'm not really sure what your confusion is. Your goal is to find the force per mass on an object which lies on a line that is perpendicular to the circle and passes through the center of the circle. Call the distance to the center of the circle R and integrate the force from each differential piece of mass (remembering that force is a vector) in which ever way you think is easiest.
 

Related Threads on Gravitational field owing to a uniform circular plate

  • Last Post
Replies
1
Views
587
  • Last Post
Replies
1
Views
712
Replies
1
Views
706
Replies
5
Views
2K
Replies
2
Views
3K
Replies
2
Views
4K
Replies
3
Views
519
Replies
3
Views
3K
Replies
5
Views
1K
  • Last Post
Replies
20
Views
4K
Top