A simple pendulum of length l₁ has periodic time 2.4 s. Another simple pendulum of length l₂ < l₁, has periodic time 1.8 s. The periodic time of simple pendulum of length (l₁ - l₂) is nearly (a) 1.2 s (b) 1.4 s (c) 1.6 s (d) 1.8 s

Answer: (c). T² ∝ l, so for length (l₁ - l₂): T² = T₁² - T₂². T² = 2.4² - 1.8² = 5.76 - 3.24 = 2.52 T = √(2.52) ≈ 1.59 ≈ 1.6 s So the answer is (c) 1.6 s.

A simple pendulum of length l₁ has periodic time 2.4 s. Another… | MHT CET 2026 (20 Apr, Shift 1)

Q9MHT CET 2026 · 20 APR · SHIFT 1Medium

Simple Pendulum

A simple pendulum of length $l_1$ has periodic time $2.4$ s. Another simple pendulum of length $l_2 < l_1$ , has periodic time $1.8$ s. The periodic time of simple pendulum of length $(l_1 - l_2)$ is nearly

Show answer and solution

Answer: (c)

$T^2 \propto l$ , so for length $(l_1 - l_2)$ : $T^2 = T_1^2 - T_2^2$ .
$T^2 = 2.4^2 - 1.8^2 = 5.76 - 3.24 = 2.52$
$T = \sqrt{2.52} \approx 1.59 \approx 1.6\text{ s}$
So the answer is (c) $1.6$ s.

Report a mistake

Simple Pendulum question from MHT CET 2026 (20 Apr, Shift 1)

More questions on Simple Pendulum