Question 654: Centre of Mass and Rotational Motion

Question

The ratio of radii of gyration of a circular ring and a circular disc, of the same mass and radius, about an axis passing through their centres and perpendicular to their planes are

Accepted Answer

$$ \because $$ $$I = M{K^2}$$ $$ 	herefore $$ $$K = \sqrt {{I \over M}} $$
I
ring
= MR
2
and I
disc
= $${1 \over 2}$$MR
2
$${{{K_1}} \over {{K_2}}} = \sqrt {{{{I_1}} \over {{I_2}}}}  = \sqrt {{{M{R^2}} \over {\left( {{{M{R^2}} \over 2}} ight)}}}  = \sqrt 2 :1$$

Answer

$$1:\sqrt 2 $$

Answer

3 : 2

Answer

2 : 1

Answer

$$\sqrt 2 :1$$

Centre of Mass and Rotational Motion

The ratio of radii of gyration of a circular ring and a circular disc, of the same mass and radius, about an axis passing through their centres and perpendicular to their planes are

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