Question

What will be velocity of a satellite revolving around the earth at a height $h$ above surface of earth if radius of earth is $R.$

• A. $R^2\sqrt{\frac{g}{R+h}}$
• B. $R\sqrt{\frac{R+h}{g}}$
• C. $R\frac{g}{(R+h{)}^2}$
• D. $R\sqrt{\frac{g}{R+h}}$

Answer 1

Answer: (D)

Velocity of satellite revolving in an orbit of radius r, $v=\sqrt{\frac{GM}{r}}$

Also $GM=g{R}^2$

$⟹v=\sqrt{\frac{g{R}^2}{r}}$

For $r=R+h$

$v=R\sqrt{\frac{g}{R+h}}$