Rotational inertia of a rod that has mass on one end

AI Thread Summary
The discussion focuses on calculating the rotational inertia of a system consisting of a metal rod and a mass attached to one end. The rod has a mass of 2 kg and a length of 4 meters, while the mass at the end is 3 kg. The rotational inertia of the rod alone is calculated to be 10.6 kg·m², but the effect of the 3 kg mass on the total inertia is unclear. It is noted that the total rotational inertia of the system can be found by summing the inertia of the rod and the inertia of the mass treated as a point particle at the end of the rod. Understanding how to combine these components is crucial for solving the problem accurately.
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Homework Statement


a 3 kg mass is on the end of a metal rod which is pivoted at one end. the mass of the rod is 2kg its length is 4 meters

Homework Equations


I=(ML^2)/3

The Attempt at a Solution


the rotational inertia of the rod itself is 10.6 but i don't know how the 3kg mass at the end would effect things
 
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xd14 said:

Homework Statement


a 3 kg mass is on the end of a metal rod which is pivoted at one end. the mass of the rod is 2kg its length is 4 meters

Homework Equations


I=(ML^2)/3

The Attempt at a Solution


the rotational inertia of the rod itself is 10.6 but i don't know how the 3kg mass at the end would effect things
Assuming the mass at the end has negligible size , what is the I of a particle of mass m about a pivot point , and then note the I of the rod-mass system is the sum of the I's of its parts.
 
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