AP EAMCET Engineering 2018 Apr 24 Shift 1 Paper

The tension is maximum at the bottom of the vertical circle.
The expression of the maximum tension is,
T1=

mv2

r

+mg
The tension is minimum at the top of the vertical circle. The expression of the minimum tension is,
T2=

mu2

r

−5mg
Given ,

T1

T2

=4
Thus,
21mg=3

mu2

r

u2=7rg
The velocity at the top is,
v=√u2−4rg
v=√7rg−4rg
v=√3rg
v=√3 (

5

3

)(10)
v=√50ms−1