# help

Can you help me with this mechanics problem?  Note by Kyle Finch
4 years, 9 months ago

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@Raghav Vaidyanathan the problem is in the middle.

- 4 years, 9 months ago

I have rotated the image. $\huge\ddot\smile$

- 4 years, 9 months ago

U can tell me the solution . ???

- 4 years, 9 months ago

A disc has an angular velocity?

- 4 years, 9 months ago

$\text{angular velocity}=\dfrac{\text{Relative velocity perpendicular to line joining them}}{\text{Distance between them}}$

By simple geometry, $\angle AOP=30^\circ$

Case I: $A$ is fixed to ground, so, the velocity of $P$ will be $\omega R$ at angle $120^\circ$ to the line joining $AP$, thus, $\omega_1=\dfrac{\omega R\cos 30^\circ}{\sqrt{3}R}$

Case II: $A$ is fixed to disc, in this case, velocity of $A$ will add up in relative velocity. In this case also, velocity of $A$ will be $\omega R$ at angle $60^\circ$ to the line joining $AP$. Thus, $\omega_2=\dfrac{\omega R\cos 30^\circ+\omega R\cos 30^\circ}{\sqrt{3}R}=2\omega_1\Rightarrow \dfrac{\omega_1}{\omega_2}=\dfrac{1}{2}$

- 4 years, 9 months ago

Well indeed very nice by the way how was ur mains exam

- 4 years, 9 months ago

Not too good. Getting just 275.

- 4 years, 9 months ago

Was the physics section tough??

- 4 years, 9 months ago

It was NCERTish. I must not blame questions for my marks. I don't like EM.

- 4 years, 9 months ago

So who among all of you is supposed to get the highest.

- 4 years, 9 months ago

Ronak Agrawal (on Brilliant)

- 4 years, 9 months ago

Ok just one last query what makes a problem popular on brilliant. Can u tell ronaks score

- 4 years, 9 months ago

He's getting like 315-320. The quality of problem makes it popular!

- 4 years, 9 months ago

No i m asking do the staff member decide or the moderators

- 4 years, 9 months ago

Bhavya Is getting 322.I guess??

- 4 years, 9 months ago

Yes, he does

- 4 years, 9 months ago

$\omega$

- 4 years, 9 months ago