Question

two point masses m and 3m are placed at distance r.The moment of inertia of the system about an axis passing through the centre of mass of system and perpendicular to the line joining the point masses is

ans-3\4mr2

Read 1 Solution.

as mass of both of the object r not equal  thus cm (centre of mass ) will be more towards 3m than  m

Let dist of cm from mass m be x & that from 3m be (r-x)

mx = 3m (r-x)

on solving u will get x= 3r/4  and r-x will = r/4

now cm of the system will be   = 3m(r-x)2 + mx2 =    ( 3mr2/16)+ (m9r2/16)  = 3/4 mrANS  ( on putting x = 3r/4 )

I THINK ANS SUBMITTED BY U  AGAIN HAS PROBLEM

SARIKA SHARMA 11 year ago is this solution helpfull: 74 29

Submit Your Answer


please login to submit your answer

Login Here

Register