Question

In: Physics

A playground merry-go-round is set spinning at 0.20 rev/s and then released. It slows to rest...

A playground merry-go-round is set spinning at 0.20 rev/s and then released. It slows to rest in 25 s. (a) Find the average angular acceleration of the merry-go-round during this time. (b) Assuming now that the angular acceleration is constant, how many turns does it make as it comes to rest?

Expert Solution

we have initial rotational speed as 0.20 rev/s that means

--------------------------------------- Solution of part (a) ----------------------------------------------

average angular acceleration is given by

So average angular acceleration of the merry-go-round is 0.016 rad/s2

---------------------------------- Solution of part b -------------------------------------------

To calculate the number of turn we have

To calculate the number of turns we have to divede the angle with 2

Number of turns are

It will take 2.5 turns to come to rest

genius_generous answered 2 years ago

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