# Problem: In a science museum, a 110kg brass pendulum bob swings at the end of a 13.2m -long wire. The pendulum is started at exactly 8:00 a.m. every morning by pulling it 1.7m to the side and releasing it. Because of its compact shape and smooth surface, the pendulum's damping constant is only 0.010 rm kg/s. At exactly 12:00 noon, how many oscillations will the pendulum have completed? And what is its amplitude?

###### FREE Expert Solution

Frequency of a pendulum executing Simple harmonic motion,

$\overline{)\begin{array}{rcl}{\mathbf{f}}& {\mathbf{=}}& \frac{\mathbf{1}}{\mathbf{2}\mathbf{\pi }}\sqrt{\frac{\mathbf{g}}{\mathbf{l}}}\end{array}}$

Number of oscillations,

$\overline{)\begin{array}{rcl}{\mathbf{N}}& {\mathbf{=}}& \mathbf{f}\mathbf{t}\end{array}}$

The amplitude of a damped motion,

A)

l = 13.2 m

g = 9.8 m/s2

92% (434 ratings) ###### Problem Details

In a science museum, a 110kg brass pendulum bob swings at the end of a 13.2m -long wire. The pendulum is started at exactly 8:00 a.m. every morning by pulling it 1.7m to the side and releasing it. Because of its compact shape and smooth surface, the pendulum's damping constant is only 0.010 rm kg/s. At exactly 12:00 noon, how many oscillations will the pendulum have completed? And what is its amplitude?