Rotating diatomic - Pretty basic first year question. Workings given

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
Sign up Log in
3 replies · 2K views · last reply
elemis
Messages
162
Reaction score
1
Part v is where I'm stuck.

All relevant equations and the bit where I'm stuck are in the second attachment with my workings

Printed exam question text, parts (iv) and (v): a 2 kg object on a string whose radius doubles from 1 m to 2 m, and a rigid rotor of two masses 0.1 kg and 0.2 kg on a 1 m bar, with a hint about the centre of mass and a PLEASE TURN OVER note.

Handwritten notes on lined paper: a dumbbell diagram with masses 0.1 kg and 0.2 kg at the ends, distances 2/3 and 1/3 from the centre of mass, moment of inertia I = 0.1(2/3)^2 + 0.2(1/3)^2 = 1/15, and torque calculations 0.2 kg × 1/3 = 100 Nm and 0.1 kg × 2/3 = 200 Nm.
 
Physics news on Phys.org

Discussion

If I can find the value for L I can substitute it into the equation for L=Iw and using the known I value I can calculate w and hence the frequency (2pif=w).
 
tiny-tim said:
hi elemis! :smile:

Why are you making it so complicated?

finding ω is a straightforward centripetal acceleration question! :wink:​

i goooot itt ! Woooohoooooo ! Thank you !