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a solid sphere, a hollow sphere, and a point mass all have the same mass. a massless rod is glued to each object to form rigid systems such that the centers of mass are all the same distance from the other end of the stick. if we hang each object from the ceiling so that they are pendulums, what is the ranking of the frequency of small oscillations, from least to greatest?

User Crompy
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Answer:

The ranking of the frequency of small oscillations for the given objects, from least to greatest, is as follows:

1. Hollow sphere

2. Solid sphere

3. Point mass

To understand this ranking, let's consider the factors that affect the frequency of small oscillations for pendulum-like systems.

The frequency of small oscillations (f) for a pendulum is given by:

f = (1 / 2π) * √(g / L)

Where:

- g is the acceleration due to gravity

- L is the effective length of the pendulum (distance from the pivot point to the center of mass)

Now, let's analyze each of the given objects:

1. Hollow sphere:

The hollow sphere has the largest moment of inertia due to its mass distribution away from the axis of rotation. This leads to a larger effective length (L) when it swings as a pendulum. The larger effective length results in a smaller frequency of oscillation compared to the other objects.

2. Solid sphere:

The solid sphere has a smaller moment of inertia compared to the hollow sphere due to its mass being more concentrated towards the center of rotation. The smaller moment of inertia gives a smaller effective length (L), resulting in a slightly higher frequency of oscillation compared to the hollow sphere.

3. Point mass:

The point mass is a theoretical idealization with all the mass concentrated at a single point. It has the smallest moment of inertia and, therefore, the smallest effective length (L). As a result, it has the highest frequency of oscillation among the three objects.

Therefore, the ranking of the frequency of small oscillations, from least to greatest, is:

1. Hollow sphere

2. Solid sphere

3. Point mass

User Loneraver
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