In 1851 Jean Bernard Leon Foucault demonstrated the rotation of the earth using a pendulum 11.0 m long, which was set up in the Paris Observatory. How long would it have taken for Foucault's pendulum to make one complete swing back to its starting point if $g = 9.81 \mathrm {~m} / \mathrm { s } ^ { 2 }$ at the observatory?
A) 5.63 s
B) 2.58 s
C) 2.12 s
D) 1.79 s
E) 6.65 s

Question

In 1851 Jean Bernard Leon Foucault demonstrated the rotation of the earth using a pendulum  11.0 m  long, which was set up in the Paris Observatory. How long would it have taken for Foucault's pendulum to make one complete swing back to its starting point if $g = 9.81 \mathrm {~m} / \mathrm { s } ^ { 2 }$ at the observatory?
A)  5.63 s
B)  2.58 s
C)  2.12 s
D)  1.79 s
E)  6.65 s

Quizplus · Accepted Answer

The period of a pendulum is given by $T = 2\pi\sqrt{\frac{L}{g}}$, where $L$ is the length of the pendulum and $g$ is the acceleration due to gravity. Substituting $L = 11.0 \, \text{m}$ and $g = 9.81 \, \text{m/s}^2$ into the formula gives $T = 2\pi\sqrt{\frac{11.0}{9.81}}$, which calculates to approximately 6.65 seconds.

In 1851 Jean Bernard Leon Foucault Demonstrated the Rotation of the Earth