Solving Omega in Angular Velocity Equations: A Test Prep for Sarah

AI Thread Summary
The discussion focuses on understanding the use of omega in angular velocity equations in preparation for a physics test. Key equations include substituting linear variables with their angular counterparts, such as replacing velocity (v) with angular velocity (ω) and acceleration (a) with angular acceleration (α). Important rotational equations are provided, including ω = ω₀ + αt and θ = θ₀ + ω₀t + ½αt². The conversation emphasizes the need to familiarize oneself with these equations for effective problem-solving. Mastering these concepts is crucial for success in the upcoming test.
sarahowen
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we are just about to take a test in physis.. I am quite scared. i have revised on all the topics required but i don't get the use of omega in angular velocity equations. what is the equation and when do i need to use it?
sarah
 
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well - u can take ur normal kinematics equation and replace v with omega.
like...

<br /> \theta = \theta_0 + \omega t + \alpha t<br />

alpha is the angular acceleration.
 
Just learn

v=rw

w= 2.pi.f = 2.pi / T

f = 1/T =w / 2.pi

a = v^2/r = rw^2

F=mv^2/r = mrw^2
 
Replace v by \omega

a by \alpha

and x by \theta

in your kinematics equations to get the rotational equations!

\omega = \omega_0 + \alpha t
\theta = \theta_0 + \omega_0 t + \frac{1}{2}\alpha t^2
\omega^2 = \omega_0^2 + 2\alpha\theta

And the Equations posted by Briton are also very important
 
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