Physics-
General
Easy
Question
Two identical uniform discs of mass m and radius r are arranged as shown in the figure. If 
is the angular acceleration of the lower disc and a cm is acceleration of centre of mass of the lower disc, then relation among 
& r is :
= 2 r
- = r
- none of these
= 2 r
= r
The correct answer is: = 2 r
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