Centripetal force/acc problem

[iamtrojan3]

Homework Statement

What angular velocity would cause a centripetal acceleration of 3 g's if the radius were 2.5 m?

i have a test 2moro on this stuff... yea i need to know =D thx

Homework Equations

i guess m(v^2)/r or mW^2r

The Attempt at a Solution

no idea. srry

 

[Edgardo]

Homework Equations

i guess m(v^2)/r or mW^2r

What is the W? And what do you calculate with mW^2r?

 

[iamtrojan3]

W is rotational velocity.. sryy for not making that clear.
(MASS)(W^2)(radius)=centripetal Force
W^2R= Centripetal Acceleration
I just plugged numbers in 29.4= W^2(2.5) and i got 3.4radian/sec for W.
this looks 2 easy... if someoen could verify please =D

 

[Edgardo]

Yes, very good, your answer is correct. But you should also write down the units, for example acceleration is in m/s^2 and radius in m. This allows you to check whether your result is correct.

For example if you calculated W as something with 1/s^2, you know you made a mistake because the unit must be 1/s (or radian/sec).

 

[iamtrojan3]

thanks tons edgardo!