Question

NEED HELP!! oscilations giving medal

Answer 1

We need use the concept of physical pendulum here. Are you familiar?

Answer 2

a little bit, maybe if i look at solution i will understand it

Answer 3

Wait, I got a link here. Should help you(hope)
http://hyperphysics.phy-astr.gsu.edu/hbase/pendp.html

Answer 4

If you can understand, how\[T = 2\Pi \sqrt{\frac{ I }{ mgl }}\]
Its fine.

Answer 5

Okay, I cannot calculate everything. But can give you the procedure
1. The original disc:
I- find out the moment of inertia about the axis passing through the point of suspension.
L- length of the line joining point of suspension and center of mass.\

2. After circular part has fallen:
I- find out new moment of inertia by subtracting the moment of inertia of fallen part.
L- it is the same way now, but the center of mass has changed. Find it out and then the length.
Substitute in the formula, get the time period..
Really a lengthy one to solve.....

Answer 6

thx

Answer 7

Welcome:)

Answer 8

where did u find this question?@denis1206
its awesome..!

Answer 9

thanks, a friend send me via email @souvik

Answer 10

did you know the answer?

Answer 11

no

Answer 12

oh!

Answer 13

The method is just as @koushik_ksv explained above. The moment of inertia of the broken disc can be found out as told above by subtracting the moment of inertia of the broken part from that of complete disc about the point of suspension.

For finding 'l' the distance of c.m. from point of suspension of the broken disc, we will first need the position of the c.m. of the broken disc.

You may check this post if do not know how it is done (i have found out c.m. for disc of radius 2R here and not R)

http://openstudy.com/users/serikmb#/updates/51b1a27be4b06ee3ee277eae