An annular disc has a mass m, inner radius R and outer radius

An annular disc has a mass m, inner radius R and outer radius 2R. The disc rolls on a flat surface without slipping. If the velocity of the center of mass is v, the kinetic energy of the disc is

I =	5mr²
	2

K.E. = (K.E.) _translation + (K.E.) _Rotation

=		1	mv² +	1	Iω²
		2		2

Where V = 2 R ω

⇒ ω =	V
	2R

∴ K.E. =		1	mv² +	5mV²
		2		16

K.F. =	13mV²
	16