Question

Two satellites A and B go around planet P in circular orbits having radius 4R and R respectively. If the speed of satellite A is $ 3\upsilon $ then the speed of satellite B will be :

• A. $ 6\upsilon $
• B. $ 9\upsilon $
• C. $ 3\upsilon $
• D. none of these

Answer 1

Answer: (A)

Orbital speed of sattelite $ \upsilon =\sqrt{\frac{GM}{r}} $ $ \therefore $ $ \frac{{{\upsilon }_{1}}}{{{\upsilon }_{2}}}=\sqrt{\frac{{{r}_{2}}}{{{r}_{1}}}} $ $ \frac{3\upsilon }{{{\upsilon }_{2}}}=\sqrt{\frac{R}{4R}}\Rightarrow \frac{3\upsilon }{\upsilon }=\frac{1}{2} $ $ {{\upsilon }_{2}}=6\upsilon $