Assertion: The speed of revolution of an artificial satellite revoving very near the earth is `8kms^(-1)`.
Reason: Orbital velocity of a satellite, becomes independent of height near earth.

Options

A. If both the assertion and reason are true and reason is a true explantion of the assertion.
B. If both the assertion and reason are true but the reason is not true the correct explantion of the assertion.
C. If the assertion is true but reason false
D. If both the assertion and reason are false.

Answer

A

Explanation

`v_(0)=R_(e)sqrt(g/(R_(e)+h))`
For satellite revolving very near to earth `R_(e)+h=R_(e)`
As `(h lt lt R)`
`v_(0)=sqrt(R_(e)g) ~=sqrt(64xx10^(5)xx10)=8xx10^(3)m//s=8kms^(-1)`
Which is independent of height of a satellite.