Acircular disc of radius 100 mm and mass 1 kg, initially

Acircular disc of radius 100 mm and mass 1 kg, initially at rest at position A, rolls without slipping down a curved path as shown in figure. The speed v of the disc when it reaches position B is _________ m/s.
Acceleration due to gravity, g = 10 m/s².

Conservation of energy
Total (KE + PE) = const.
(KE + PE)_A = (KE + PE)_B

0 + 30 × mg =	1	MV² +	1	Iω² + 0
	2		2

30 × 10 =	1	× 1 × V² +	1	×	1	× 1 × v²
	2		2		2

I =	mr²	, ω =	V
	2		I

30 × 10 =	3	= V²
	4

V = 20 m/s