Question

A simple pendulum while oscillating rises to a maximum vertical height of 7 cm from its rest position where it reaches its extreme position on one side. The mass of the bob of simple pendulum is 400 g and g = 10 m/s². The total energy of the simple pendulum at any instant while oscillating is:
(a) 0.28 J
(b) 2.8 J
(c) 28 J
(d) 28000 J

April 24, 2024

Answer

(a) 0.28 J

Reason — Given,

m = 400 g = 0.4 kg

g = 10 m/s²

h = 7 cm = 0.07 m

The potential energy of the pendulum at its extreme position (maximum height) is : mgh

and kinetic energy at this point = 0

Substituting we get,

Total energy = PE + KE = mgh + 0 = (0.4 x 10 x 0.07) + 0 = 0.28 J

💡 Some Related Questions

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