To determine the velocity of a satellite when it is moved to an orbital radius of \(5r\), we can use the formula for the orbital velocity of a satellite in circular orbit, which is given by:
\[ v = \sqrt{\frac{GM}{r}} \]
where \(G\) is the gravitational constant, \(M\) is the mass of the Earth, and \(r\) is the orbital radius.
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At radius \(r\), the velocity is: \[ v = \sqrt{\frac{GM}{r}} \]
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At radius \(5r\), the new velocity \(v'\) can be calculated as: \[ v' = \sqrt{\frac{GM}{5r}} = \sqrt{\frac{1}{5}} \sqrt{\frac{GM}{r}} = \frac{1}{\sqrt{5}} v \]
Therefore, if the satellite is moved to an orbital radius of \(5r\), the new velocity becomes:
\[ v' = \frac{1}{\sqrt{5}} v \]
The correct response is: A) \( \frac{1}{\sqrt{5}} v \).