Physics Review Problem Help

[sandra123123]

A test subject in a centrifuge revolves along a circle of radius r = 10m. What must be the angular velocity of the centrifuge so that the subject experiences 9 g's? (I did this myself and got 2.96 rad/sec. I just need -assuming my answer is okay - help with the next two. Any help is greatly appreciated^^ )

If the centrifuge is "spun up" to this angular velocity from rest over a period of 75 seconds, what is the angular acceleration of the centrifuge?

How many revolutions does the subject make during the spin-up?

[Hypognosis]

Sandra

The first one is more straightforward than you think
2.96/75 but the units are rad "per second, per second" (or rad/s^2, or rad.s^-2 for short)

The second is analagous to linear acceleration s=ut + 1/2 a.t^2
u=0, so it's just 1/2.a.t^2 and you've just calculated a.
However, that answer is in radians but the question specifies revolutions, so convert by dividing by 2*pi.

You didn't state what was the "agreed value" for "g" (probably varies according to teacher). We always used 9.81, so I immediately got 2.97 where you got 2.96, hence I've not worked through the numbers for you. Hope it helps.

[sandra123123]

Thank you so much! I was totally over-thinking it :P

[factor-fiction]

Morning sandra- have you seen the answers you were given on your other two questions from last week?