Does a rigid object in uniform rotation about a fixed axis satisfy the first and second conditions for equilibrium?

Explanation:

a rigid object in uniform rotation about a fixed axis does not satisfy both the condition of equilibrium .

First condition of equilibrium is that net force on the body should be zero.

or F net = 0

A body under uniform rotation is experiencing a centripetal force all the time so F net ≠ 0

So first condition of equilibrium is not satisfied.

Second condition is that , net torque acting on the body  must be zero.

In case of a rigid object in uniform rotation , centripetal force is applied towards the centre ie  towards the  line joining the body under rotation with the axis .

F is along r

torque = r x F

= r F sinθ

θ = 0 degree

torque = 0

Hence 2nd condition is fulfilled.

i think they are all correct

explanation:

they seem good

there is no correct list among the choices you've provided.

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-- baby human

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-- flute

-- soprano singer

-- trumpet

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-- bass singer

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since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.