Question

Four pendulums A, B, C and D are suspended from the same elastic support as shown in figure. A and C are of the same length, while B is smaller than A and D is larger than A. If A is given a transverse displacement,

• A. D will vibrate with maximum amplitude
• B. C will vibrate with maximum amplitude
• C. B will vibrate with maximum amplitude
• D. All the four will oscillate with equal amplitude

Answer 1

Answer: (B)

C will vibrate with maximum amplitude

Answer 2

Since length of pendulums A and C is same and $T = 2\pi\sqrt{\frac{L}{g}},$ hence their time period is same and they will have same frequency of vibration due to it a resonance will take place and the pendulum C will vibrate with maximum amplitude.