Question

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

• A. $4099\text{kmph}$
• B. $3099\text{kmph}$
• C. $1099\text{kmph}$
• D. $2099\text{kmph}$

Answer 1

The correct option is C $1099\text{kmph}$

Given, the radius of the orbit, $R=4200km$
The time taken to revolve around the Earth, $T=24hr\left(1day\right)$
The speed of the satellite, $v=\frac{\text{Circumference of the orbit}}{\text{Time taken}}$
$=\frac{2\pi R}{T}$
$=\frac{2\times 3.14\times 4200\text{km}}{24\text{hr}}$
$=1099\text{km}{\text{hr}}^{-1}$
$=1099\text{kmph}$