JEE Physics · Hard

Gravitation: Period at Earth's Surface MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow
Period at Earth's SurfaceHardQuestion 30735

Question

A satellite grazes Earth's surface (h ≈ 0). Its orbital period is approximately: (g = 10, R = 6.4×10⁶ m)
  1. A
    5060 s ≈ 84 min
    Correct
  2. B
    24 hours
  3. C
    1 hour
  4. D
    6 hours

Correct answer

5060 s ≈ 84 min

Explanation

T = 2π√(R/g) = 2π√(6.4×10⁶/10) = 2π×800 = 5027 s ≈ 84 min. All low Earth orbital periods are approximately 90 minutes.