Question

Assume that a satellite is revolving around Earth in a circular orbit almost close to the surface of Earth. The time period of revolution of satellite is $($Radius of earth is 6400 km, $g=$ 9.8 $m{s}^{-2})$

• A. $5077sec$
• B. $5068min$
• C. $24hour$
• D. $1year$

Answer 1

The correct option is A $5077sec$

Time period of the satellite is given by: $T=2\pi \sqrt{\frac{r}{g}}$
Almost close to surface of Earth $⟹r=R_e$
$\therefore$ Time period, $T=2\pi \sqrt{\frac{6400\times {10}^3}{9.8}}$
Time period, $T=5077$ seconds