Question on total moment of inertia

AI Thread Summary
The discussion revolves around calculating the force exerted by each spout of a lawn sprinkler based on its moment of inertia and rotational motion parameters. The sprinkler has a moment of inertia of 9.10 x 10^-2 kg·m² and takes 2.60 seconds to reach a final speed of 3.0 revolutions per second. To solve for the force, one can first determine the angular acceleration using the given speed and time. With the moment of inertia and angular acceleration, the torque can be calculated, which can then be used to find the force exerted by each spout. The key takeaway is that the relationship between moment of inertia, angular acceleration, and force is crucial for solving the problem.
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Homework Statement



A lawn sprinkler has three spouts that spray water, each r = 15.5 cm long. As the water is sprayed, the sprinkler turns around in a circle. The sprinkler has a total moment of inertia of 9.10 10^-2 kg · m2. If the sprinkler starts from rest and takes 2.60 s to reach its final speed of 3.0 rev/s, what force does each spout exert on the sprinkler?

Homework Equations


I= N * M * R ^2, not sure about N


The Attempt at a Solution


The radius is .155 m, I = 9.10 * 10^-2 , I can't figure out how to get M, do i use the fact that it takes "takes 2.60 s to reach its final speed of 3.0 rev/s" , please lay it out for me , thanks
 
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You have a speed and a time, which means you can calculate acceleration. You're also given a moment of inertia, which means you can find something else useful.

Then given that other useful piece of information, you should be able to find your answer.
 
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