# Conceptual doubt in angular velocity

#### Tanya Sharma

The equation $\frac{dθ}{dt}=-\frac{usinθ}{r}$ is integrable for all v/u>1 after you substituted for r. Use $\sinθ=2\frac{\tan(θ/2)}{1+\tan^2(θ/2)}$ and integral with substitution tan(θ/2) =z. (You can cheat ... with Wolframalpha)

ehild
You are simply awesome

I got the answer . Just when I was thinking that the integral was too much for me ,you plucked out something superb from your bag of tricks .

I had calculated the integral for the special case v/u =2 as told by Chet in post#24 ,but wasn't able to get the general result .

I did the integration as suggested by you without using Wolfram and got the result in a couple of minutes .

ehild...You rock!!!

#### ehild

Homework Helper
But your solution was simply ingenious !

ehild

"Conceptual doubt in angular velocity"

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