Doubt from moment of inertia

Question 3 and 4

For 4th i think , it should be C

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Yes thank you

What about question 3

Answer is 31ml^2/12

I’m sorry , i did a mistake there
The distance between the centre of disc and rectangle is 3R/2 and i have written there it as 2R
Please ignore post#5

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Can you tell me how you got Mr^2/4 for disc and M(3R/2)^2

Oh sorry I got it please neglect earlier post

In question 5 a part i am getting ml^2/2 which is correct but i am getting b part wrong answer i know that radius of gyration is equal to K=(I/M)^1/2 according to that i am getting k=1/root2 but answer is 1/root6

For radius of gyration’s calculation you have to write I=(Total mass of system) k²
And hence
K=root(I / total mass )
Here instead of total mass=3m you have written it to be m and that’s why you are getting 1/2 instead of 1/6

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Oh thanks

Question 6 both parts

I wasn’t able to understand the part b of this question .
What is point P !
If you’ll be able to understand it then do let me know

For part A ,

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Question 8

I’m getting option d

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Question 2

Is ABCD Aanswer for 2

Yes show your solution

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Can you help me how you got M.I as ml^2/4 for 1 and 3 axis ?