Examsnet
Unconfined exams practice
Home
Exams
Banking Entrance Exams
CUET Exam Papers
Defence Exams
Engineering Exams
Finance Entrance Exams
GATE Exam Practice
Insurance Exams
International Exams
JEE Exams
LAW Entrance Exams
MBA Entrance Exams
MCA Entrance Exams
Medical Entrance Exams
Other Entrance Exams
Police Exams
Public Service Commission (PSC)
RRB Entrance Exams
SSC Exams
State Govt Exams
Subjectwise Practice
Teacher Exams
SET Exams(State Eligibility Test)
UPSC Entrance Exams
Aptitude
Algebra and Higher Mathematics
Arithmetic
Commercial Mathematics
Data Based Mathematics
Geometry and Mensuration
Number System and Numeracy
Problem Solving
Board Exams
Andhra
Bihar
CBSE
Gujarat
Haryana
ICSE
Jammu and Kashmir
Karnataka
Kerala
Madhya Pradesh
Maharashtra
Odisha
Tamil Nadu
Telangana
Uttar Pradesh
English
Competitive English
Certifications
Technical
Cloud Tech Certifications
Security Tech Certifications
Management
IT Infrastructure
More
About
Careers
Contact Us
Our Apps
Privacy
Test Index
IIT JEE Advanced 2012 Paper 1
Show Para
Hide Para
Share question:
© examsnet.com
Question : 19
Total: 60
A lamina is made by removing a small disc of diameter 2R from a bigger disc of uniform mass density and radius 2R, as shown in the figure. The moment of inertia of this lamina about axes passing through O and P is
I
O
and
I
P
respectively. Both these axes are perpendicular to the plane of the lamina. The ratio
I
O
I
P
to the nearest integer is _____.
Your Answer:
Validate
Solution:
We have
I
P
=
[
4
m
R
2
2
+
m
(
4
R
2
)
]
−
[
m
4
R
2
2
+
m
4
5
R
2
]
=
m
R
2
[
(
2
+
4
)
−
(
1
8
+
5
4
)
]
=
m
R
2
[
(
2
+
4
)
−
(
1
8
+
5
4
)
]
I
p
=
m
R
2
(
6
−
11
8
)
=
37
8
m
R
2
(1)
I
O
=
(
4
m
R
2
2
)
−
(
m
4
R
2
2
+
m
4
R
2
)
I
O
=
m
R
2
[
2
−
(
1
8
+
1
4
)
]
=
m
R
2
[
2
−
3
8
]
=
m
R
3
(
13
8
)
(2)
Dividing Eq. (1) by Eq. (2), we get the ratio
I
O
I
P
to the nearest integer as
I
P
I
O
=
37
8
13
8
~ 3
© examsnet.com
Go to Question:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Prev Question
Next Question
Examsnet