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
JEE Advanced 2020 Full Test 1 Paper 1
Show Para
Hide Para
Share question:
© examsnet.com
Question : 2
Total: 54
A glass cylindrical vessel with base concave mirror of focal length
20
c
m
is filled with two immiscible liquid of refractive index 1.5 and
1.4
.
Thickness of liquid level are
15
c
m
and 14 cm respectively. A fish is moving vertically upward along principle axis of mirror with speed of
1
c
m
∕
s
. A bird is moving along vertically downward direction with
2
c
m
∕
s
.
A
small hole is made at bottom surface of vessel. When distance of fish from pole of mirror is
10
c
m
, the rate of liquid level falling is
1
c
m
∕
s
. (focal length of concave mirror is
20
c
m
). Then, at the given instant
Velocity of image of fish formed after reflection from mirror as seen by bird is
1
c
m
∕
s
along upward direction.
Velocity of image of fish after formed after reflection of mirror as seen by bird is
1
c
m
∕
s
along downward direction
Velocity of image of fish as seen by itself is
5
c
m
∕
s
along downward direction
Velocity of image of fish as seen by itself is
5
c
m
∕
s
along vertically upward direction
Validate
Solution:
For mirror, from mirror formula
1
V
+
1
−
10
=
1
−
20
⇒
V
=
+
20
m
=
−
V
u
=
2
For spherical mirror
v
1
=
−
m
2
v
0
=
−
4
×
1
=
−
4
c
m
∕
s
Now using concept of apparent depth
v
I
B
=
1
c
m
∕
s
along downward
v
I
F
=
5
c
m
∕
s
along downward
© 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
Prev Question
Next Question