The time period of a satellite, revolving above Earth's surface at a height equal to will be (Given radius of earth ):
- A
- B
- C
- D
The time period of a satellite, revolving above Earth's surface at a height equal to will be (Given radius of earth ):
Correct answer:D
Standard Method
Given: A satellite revolves at a height equal to above Earth's surface, so the orbital radius is . Also, .
Find: The time period of the satellite.
Using the time period formula for a satellite:
Substituting :
At the surface of the Earth, we have
So, substituting and , we get:
Therefore, the obtained value is . However, the solution explicitly marks the correct option as D, so the answer is taken as D based on the solution authority.
Working Shown in the solution
Given: Height of satellite above Earth is , hence distance from Earth's centre is .
Find: The matching option for the time period.
The extracted working states:
and also . 4. This gives
so
This final expression corresponds to option A among the listed options, but the solution says The Correct Option is D. This is an internal provided discrepancy.
Taking the orbital radius as instead of . This is wrong because the satellite is at a height equal to Earth's radius above the surface, so the distance from Earth's centre is . Always use centre-to-satellite distance in orbital formulas.
Using directly at the satellite's location as if it were the surface value. This is wrong because the relation used in the solution is the surface relation . Use it only to replace in terms of Earth's radius .
Matching the computed expression to the wrong option without checking the option list. The working gives , which matches option A, while the page labels option D. Always compare the final expression with the listed options and note any provided mismatch.
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