A) \[\frac{R}{2}\]
B) R
C) 3R
D) 6R
Correct Answer: B
Solution :
Orbital speed \[{{v}_{1}}=\sqrt{\frac{GM}{r}},\]while escape velocity \[{{v}_{c}}=\sqrt{\frac{2GM}{R}}\] But \[{{v}_{0}}=\frac{1}{2}{{v}_{c}}\]\[\therefore \]\[\sqrt{\frac{GM}{r}}=\sqrt{\frac{GM}{r}}\Rightarrow r=2R\] \[\therefore \]Height above earth is \[2R-R.\] Hence, the correction option is [b].You need to login to perform this action.
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