AP EAMCET Engineering 21 Sep 2020 Shift 1 Paper

The given situation is shown in the following figure.When cylinder reaches at bottom, then its whole potential energy is converted into its rotational kinetic energy and linear kinetic energy of its centre of mass.
Hence, Mgh=‌

1

2

Iω2+‌

1

2

MvCOM2
[∵I=‌

MR2

2

and ω=‌

vCOM

R

]
=‌

MvCOM2

4

+‌

MvCOM2

2

⇒‌‌Mgh=‌

3

4

MvCOM2
⇒‌‌vCOM2=‌

4gh

3

⇒‌‌vCOM=√‌

4gh

3