Question

A simple pendulum 50 cm long is suspended from the roof of a cart accelerating in the horizontal direction with acceleration 7 m/S². The period of small oscillations of the pendulum about its equilibrium position is (g = 9.8 m/s²):

• A. 1.28 s
• B. 1.42 s
• C. 1.53 s
• D. 1.68 s

Answer 1

Answer: (A)

1.28 s

Answer 2

With respect to the cart, equilibrium position of the pendulum

is shown. If displaced by small angle from this position, then it will execute SHM about this equilibrium position, time period of which is

given by

T = 2π$\sqrt{\frac{L}{g_{eff}}}$

g_eff = $\sqrt{9.8^{2} + 7^{2}}$ T = 1.28 second