JEE Main 2024 Physics question
A simple pendulum is placed at a place where its distance from the earth's surface is equal to the radius of the earth. If the length of the string is 4 m, then the time period of small oscillations will be s. (Take g = π² ms⁻²)
Answer: 8
Solution
At a height equal to the radius of the earth, g′ = g/4. So T′ = 2π√(4ℓ/g) = 2π√(4 × 4/π²) = 2π × 4/π = 8 s.