A simple pendulum is made my attaching a rod of negligible mass to a 2.0 kg pendulum bob at the end. It is observed that on Earth, the period of small-angle oscillations is 1.0 second. It is also observed that on Planet X this same pendulum has a period of 1.8 seconds. How much does the pendulum bob weigh on Planet X

Respuesta :

Answer:

[tex]W = 9.081\,N[/tex]

Explanation:

The angular frequency of a simple pendulum is:

[tex]\omega = \sqrt{\frac{g}{l} }[/tex]

Where:

[tex]g[/tex] - Gravitational constant, in [tex]\frac{m}{s^{2}}[/tex].

[tex]l[/tex] - The rod length, in m.

The period of oscillation of the simple pendulum is:

[tex]T = 2\pi\cdot \sqrt{\frac{l}{g} }[/tex]

Given that the same pendulum is tested of both planets, the following relation is determined:

[tex]T_{1}^{2}\cdot g_{1} = T_{2}^{2}\cdot g_{2}[/tex]

The gravity constant on Planet X is:

[tex]g_{2} = g_{1}\cdot \left(\frac{T_{1}}{T_{2}}\right)^{2}[/tex]

[tex]g_{2} = (9.807\,\frac{m}{s^{2}})\cdot \left(\frac{1\,s}{1.8\,s} \right)^{2}[/tex]

[tex]g_{2} = 3.027\,\frac{m}{s^{2}}[/tex]

The weight of the pendulum bob on Planet X is:

[tex]W = (3\,kg) \cdot (3.027\,\frac{m}{s^{2}} )[/tex]

[tex]W = 9.081\,N[/tex]