Question Detail
Question
Calculate the length of a conical pendulum moving with a period of 5.62 s given that the string turns at a constant angle 60° to the vertical.
Correct Answer
Option D is the correct answer.
Detailed Explanation
For a conical pendulum, the period T = 2π√(L cosθ / g). Given T = 5.62 s, θ = 60°, g = 9.8 m/s² (assumed). So L = (T² g) / (4π² cosθ) = (5.62² × 9.8) / (4π² × 0.5). 5.62² = 31.5844, times 9.8 = 309.527, denominator 4π²×0.5 = 2π² = 2×9.8696 = 19.7392. So L = 309.527 / 19.7392 = 15.68 m ≈ 16 m.
Hint
Use the formula for the period of a conical pendulum.