A circular disc reaches from top to bottom of an inclined plane of length L . When it slips down the plane,…

A circular disc reaches from top to bottom of an inclined plane of length L. When it slips down the plane, it takes time  t1. When it rolls down the plane, it takes time t2. The value of t2t1 is 3x. The value of x will be

Solution

If disk slips on inclined plane, then its acceleration, a1=gsinθ
L=12a1t12
t1=2 La1 i

If disk rolls on inclined plane, its acceleration,
a2=gsinθ1+ImR2
a2=gsinθ1+mR22 mR2
a2=23gsinθ
Now L=12a2·t22
t2=2 La2 ii

Now, t2t1=a1a2=32
x=2

Asked in: JEE Main 2021 (20 Jul Shift 1)

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