If the earth were to suddenly contract to half of its present radius, what would be the duration of the day?

The angular momentum of a moving body remains constant, if

Two fly wheels are connected by a non-slipping belt as shown in the figure. $I_1=4 \mathrm{~kg} \mathrm{~m}^2, r_1=20 \mathrm{~cm}$, $\mathrm{I}_2=20 \mathrm{~kg} \mathrm{~m}^2$ and $\mathrm{r}_2=30 \mathrm{~cm}$. A torque of 10 Nm is applied on the smaller wheel. Then match the entries of column I with appropriate entries of column II.

I	Quantities	II	Their numerical Values (in SI units)
(a)	Angular acceleration of smaller wheel	(i)	$\frac{5}{3}$$\frac{5}{3}$(5)/(3)
(b)	Torque on the larger wheel	(ii)	$\frac{100}{3}$$\frac{100}{3}$(100)/(3)
(c)	Angular acceleration of larger wheel	(iii)	$\frac{5}{2}$$\frac{5}{2}$(5)/(2)

A ceiling fan is rotating around a fixed axle as shown. The direction of angular velocity is along .......... .