Question 208: Oscillations

Question

A pendulum is suspended by a string of length 250 cm. The mass of the bob of the pendulum is 200 g. The bob is pulled aside until the string is at 60$$^\circ$$ with vertical as shown in the figure. After releasing the bob, the maximum velocity attained by the bob will be ____________ ms$$-$$1. (if g = 10 m/s2)

Accepted Answer

$${1 \over 2}m{v^2} = mgl(1 - \cos 	heta )$$
$$ \Rightarrow v = \sqrt {2gl(1 - \cos 	heta )} $$
$$ = \sqrt {2 	imes 10 	imes 2.5 	imes {1 \over 2}} $$
$$ = 5$$ m/s

Oscillations

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