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Vaishnavi
Subject: Physics
, asked on 11/4/18
28
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)
Answer
1
Vaishnavi
Subject: Physics
, asked on 11/4/18
Solve this:
22. A monochromatic light passes through a glass
slab (
μ
= 1.5) of thickness 9 cm in time t
1
.If it takes
a time t
2
to travel the same distance through water
(
μ
= -4/3). The value of (t
1
-t
2
) is
l) 5 x 10
-11
sec 2) 5 x 10
-8
sec
3) 2.5 x 10
-10
sec 4) 5 x 10
-10
sec
Answer
1
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve this ..
Q.58. The focal lengths of the objective and the eyepiece of a microscope are 2 cm and 7 cm respectively. The separation between the lenses is 20 cm. At what distance from the objective should the object be placed to get the image at a distance of 25 cm from the eyepiece?
(a) 3.219 cm
(b) 2.319 cm
(c) 3.291 cm
(d) None of these
Answer
1
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve this..
Q.54. A ray of light incident at an angle 45
°
on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45
°
(b) 180
°
(c) 135
°
(d) None of these
Answer
2
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve this.
Q57. One of the slit-width in Young's double -slit experiment is double the other. If the amplitude of the light wave is proportional to slit-width, then the ratio of the maximum and minimum intensity in the interference pattern is
(a) 3 : 1 (b) 6 : 1
(c) 9 : 1 (d) 12 : 1
Q58. The focal lengths of the objective and the eyepiece of a microscope are 2cm and 7cm respectively. The separation between the lenses is 20cm. At what distance from the objective should the object be placed to get the image at a distance of 25 cm from the eyepiece?
(a) 3.219 cm (b) 2.319 cm
(c) 3.291 cm (d) None of these
Answer
2
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve this.
Q.53. A small solid sphere falls with a terminal velocity of 30 m/sec. In vacuum, the terminal velocity will be
(a) less than 30 m/s
(b) more than 30 m/s
(c) equal to 30 m/s
(d) no terminal velocity
Q.54. A ray of light incident at an angle 45
°
on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45
°
(b) 180
°
(c) 135
°
(d) None of these
Answer
1
Poonam Tripathi
Subject: Physics
, asked on 5/4/18
What and how please
Q.
An object is placed between two plane mirrors inclined at some angle to each other. If the number of images formed is 7 then the angle of inclination is
(1) 15
°
(2) 30
°
(3) 45
°
(4) 60
°
Answer
1
Aparna Sahu
Subject: Physics
, asked on 2/4/18
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(
a
)
5
°
(
b
)
4
°
(
c
)
3
°
(
d
)
2
°
Answer
1
Aparna Sahu
Subject: Physics
, asked on 2/4/18
Q.40. The power of a lens in air
μ
g
l
a
s
s
=
1
.
5
is + 3 D. The power of the same lens in water
μ
w
a
t
e
r
=
4
/
3
is
(a) + 1 D
(b) + 2 D
(c) + 1.5 D
(d) + 1.7 D
Answer
1
Mitali
Subject: Physics
, asked on 27/3/18
Solution please of 6 and 7. answer of 6 is root2.g/10 m/s^2 and of 7 it is pi(root1.2 +1)/rootg = 2.1 sec
Q6. A simple pendulum suspended through the celling of a car rest oscillates with time period 2 seconds car suddenly starts moving with acceleration a
0
then time period changes to 1.99 seconds. Find a
0
.
Q7. A 0.1kg ball is attached to string 1.2 m long and suspended as a simple pendulum. At a point 0.2 m below the point of suspension a peg is placed.which the string hits when the pendulum comes down. If the mass is pulled a small distance to one side and released what will be the time period of the motion (g = 10 m/sec
2
)
Answer
1
Mayank Deshpande
Subject: Physics
, asked on 25/3/18
thank you
Q. If y
1
= 5 (mm) sin
π
t is equation of oscillation of source S
1
and y
2
= 5 (mm) sin (
π
t +
π
/6) be that of S
2
and it takes 1 sec and 1/2 sec for the transverse waves to reach point A from sources S
1
and S
2
respectively then the resulting amplitude at point A, is :-
1
2
+
3
mm
(2)
5
3
/
2
mm
(3) 5 mm (4)
5
2
mm
Answer
1
Swathi
Subject: Physics
, asked on 24/3/18
A ray of light is incident at 50
o
on the middle of one of the 2 mirrors arrranged at an angle of 60
o
b/w them. The ray then touches the second mirror,get reflected back to the first mirror at an angle of incidence of
50
o
60
o
70
o
4. 80
o
please answer the above question in detail and do solve it
Answer
1
Chirag Kaushik
Subject: Physics
, asked on 17/3/18
Can you help me to solbe this question
Answer
2
Shubhrajyoti Ghosh
Subject: Physics
, asked on 16/3/18
No links please
Q.9. The object distance and the image distance from the focus of a spherical mirror are x and y respectively. Establish the relation between x — y. Which mirror is used as a view finder in a motor car?
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 16/3/18
No links please
Q). Explain resolving power of a microscope. Compare between telescope and microscope.
Answer
1
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Next
What are you looking for?
22. A monochromatic light passes through a glass
slab ( = 1.5) of thickness 9 cm in time t1 .If it takes
a time t2 to travel the same distance through water
( = -4/3). The value of (t1-t2) is
l) 5 x 10-11 sec 2) 5 x 10-8 sec
3) 2.5 x 10-10 sec 4) 5 x 10-10 sec
Q.58. The focal lengths of the objective and the eyepiece of a microscope are 2 cm and 7 cm respectively. The separation between the lenses is 20 cm. At what distance from the objective should the object be placed to get the image at a distance of 25 cm from the eyepiece?
(a) 3.219 cm
(b) 2.319 cm
(c) 3.291 cm
(d) None of these
Q.54. A ray of light incident at an angle 45 on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45
(b) 180
(c) 135
(d) None of these
Q57. One of the slit-width in Young's double -slit experiment is double the other. If the amplitude of the light wave is proportional to slit-width, then the ratio of the maximum and minimum intensity in the interference pattern is
(a) 3 : 1 (b) 6 : 1
(c) 9 : 1 (d) 12 : 1
Q58. The focal lengths of the objective and the eyepiece of a microscope are 2cm and 7cm respectively. The separation between the lenses is 20cm. At what distance from the objective should the object be placed to get the image at a distance of 25 cm from the eyepiece?
(a) 3.219 cm (b) 2.319 cm
(c) 3.291 cm (d) None of these
Q.53. A small solid sphere falls with a terminal velocity of 30 m/sec. In vacuum, the terminal velocity will be
(a) less than 30 m/s
(b) more than 30 m/s
(c) equal to 30 m/s
(d) no terminal velocity
Q.54. A ray of light incident at an angle 45 on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45
(b) 180
(c) 135
(d) None of these
Q. An object is placed between two plane mirrors inclined at some angle to each other. If the number of images formed is 7 then the angle of inclination is
(1) 15 (2) 30
(3) 45 (4) 60
(a) + 1 D
(b) + 2 D
(c) + 1.5 D
(d) + 1.7 D
Q6. A simple pendulum suspended through the celling of a car rest oscillates with time period 2 seconds car suddenly starts moving with acceleration a0 then time period changes to 1.99 seconds. Find a0.
Q7. A 0.1kg ball is attached to string 1.2 m long and suspended as a simple pendulum. At a point 0.2 m below the point of suspension a peg is placed.which the string hits when the pendulum comes down. If the mass is pulled a small distance to one side and released what will be the time period of the motion (g = 10 m/sec2)
Q. If y1 = 5 (mm) sin t is equation of oscillation of source S1 and y2 = 5 (mm) sin ( t + /6) be that of S2 and it takes 1 sec and 1/2 sec for the transverse waves to reach point A from sources S1 and S2 respectively then the resulting amplitude at point A, is :-
(2) mm
(3) 5 mm (4) mm
- 50o
- 60o
- 70o
4. 80oplease answer the above question in detail and do solve it
Q.9. The object distance and the image distance from the focus of a spherical mirror are x and y respectively. Establish the relation between x — y. Which mirror is used as a view finder in a motor car?
Q). Explain resolving power of a microscope. Compare between telescope and microscope.