Question

A satellite is moving in a circular orbit of radius 4200 km around the earth. What is its speed if it takes one day to complete one revolution?

• A. $4200km{h}^{-1}$
• B. $3100km{h}^{-1}$
• C. $2200km{h}^{-1}$
• D. $1100km{h}^{-1}$

Answer 1

The correct option is D $1100km{h}^{-1}$

A satellite is orbiting around the earth in a circular orbit of radius 4200 km.
Total circumference of the orbit $=2\pi r$
Time period of revolution, $T=1day=24hour.$
Speed of the satellite $=\frac{2\pi r}{T}$
$=2\times \frac{22}{7}\times 4200\times \frac{1}{24}$
$=1100km{h}^{-1}$
Hence, the speed of the satellite is given as $1100km{h}^{-1}$