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Rotational energy

Three point masses lie along a rigid, massless rod of length L = 5.61 m :

- Two particles, both of mass m = 2.1 kg, lie on opposite ends of the rod.
- Mass M = 7.29 kg is in the center of the rod.

Assume the rod lies along the x-axis, and rotates about the y-axis. about a point 1.28 m from one end at constant angular speed ω = 5.38 rad/s.

Find the kinetic energy of this system



could someone explain the ( about a point 1.28m from one end) . dose the distance 1.28 contribute any Kinetic energy to the system?
thank you so much
 

Answers and Replies

Doc Al
Mentor
44,827
1,083
Use the distance from the axis of rotation and the angular speed to find the linear speed of each point mass. Use that to find their kinetic energy.
 

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