AP EAPCET 06-Jul-2022 Shift 2 Paper

The given situation is shown belowIf a be the acceleration of block, then by equation of motion,
mg−T=ma.....(i)
⇒ We know that, torque (τ) in the disc
τ=Iα
⇒T⋅R=‌

MR2

2

×α
(∵τ=T⋅R. and I=‌

MR2

2

)
T=‌

MRα

2

......(ii)
From Eqs. (i) and (ii), we get
‌mg−‌

MRα

2

=ma
⇒mg−‌

MR

2

⋅‌

a

R

=ma⇒mg−‌

ma

2

=ma
⇒mg=‌

ma

2

+ma⇒mg=(‌

M

2

+m)a
⇒a=‌

mg

m+‌ M 2