Asolid uniform disk with a mass m and a radius r is pivoted around a horizontal axis through its center, and a small object with mass m is attached to the rim of the disk. if the disk is released from rest with the small object at the end of a horizontal radius, find the angular velocity of the small object at the bottom.

Explanation:

By conservation of energy:

The initial energy of the system is:

The final energy of the system is:

Solving for ω:

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

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