The angular diameter of the Sun is measured to be $1920''$. If the distance of the Sun from the Earth is $1.496 \times 10^{11} \ m$,calculate the diameter of the Sun. (Given: $1'' = 4.85 \times 10^{-6} \ rad$)

Calculate the angle of $(a)$ $1^{\circ}$ (degree),$(b)$ $1^{\prime}$ (minute of arc),and $(c)$ $1^{\prime \prime}$ (second of arc) in radians. Use $360^{\circ} = 2\pi \text{ rad}$,$1^{\circ} = 60^{\prime}$,and $1^{\prime} = 60^{\prime \prime}$.

What is the accuracy of an atomic clock?

The distance of the Sun from Earth is $1.5 \times 10^{11} \,m$ and its angular diameter is $2000 \,s$ when observed from the Earth. The diameter of the Sun will be ...........

It is a well-known fact that during a total solar eclipse,the disk of the Moon almost completely covers the disk of the Sun. From this fact and the information given below,determine the approximate diameter of the Moon.
Distance of the Moon from the Earth $= 3.84 \times 10^{8} \; m$
Distance of the Sun from the Earth $= 1.496 \times 10^{11} \; m$
Diameter of the Sun $= 1.39 \times 10^{9} \; m$

How is time regulated in a wristwatch and a cesium clock?