question_answer

A solid sphere of mass M and radius R is divided into two unequal parts. The first part has a mass of \[\frac{7M}{8}\]and is converted into a uniform disc of radius 2R. The second part is converted into a uniform solid sphere. Let \[{{I}_{1}}\] be the moment of inertia of the disc about its axis and \[{{I}_{2}}\]be the moment of inertia of the new sphere about its axis. The ratio \[{{I}_{1}}/{{I}_{2}}\] is given by :                                           [JEE Main 10-4-2019 Afternoon]

A)   185                

B)        65

C)   285                

D)        140

Correct Answer: D

Solution :

[d]