The time period of a simple pendulum is 2 s. If its length is increased by 4 times, then its period becomes:
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The time period of a simple pendulum is 2 s. If its length is increased by 4 times, then its period becomes:

G1 Physics · Accepted Answer

Step 1: The simple-pendulum period is T = 2π√(L/g), hence T ∝ √L. Step 2: Increasing length fourfold gives L′ = 4L. Step 3: T′/T = √(L′/L) = √4 = 2. Step 4: New period T′ = 2 × 2 s = 4 s. Final answer: (D) 4 s.