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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
$\xb0$
on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45
$\xb0$
(b) 180
$\xb0$
(c) 135
$\xb0$
(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
$\xb0$
(2) 30
$\xb0$
(3) 45
$\xb0$
(4) 60
$\xb0$
Answer
1
Aparna Sahu
Subject: Physics
, asked on 2/4/18
$AthinprismPwithanangle4\xb0andmadeofglassofindex1.54iscombinedwithanotherprismmadeofglassofindex1.72toproducedispersionwithnodeviation.TheangleofprismQis\phantom{\rule{0ex}{0ex}}\left(a\right)5\xb0\phantom{\rule{0ex}{0ex}}\left(b\right)4\xb0\phantom{\rule{0ex}{0ex}}\left(c\right)3\xb0\phantom{\rule{0ex}{0ex}}\left(d\right)2\xb0$
Answer
1
Aparna Sahu
Subject: Physics
, asked on 2/4/18
Q.40. The power of a lens in air
$\left({\mu}_{glass}=1.5\right)$
is + 3 D. The power of the same lens in water
$\left({\mu}_{water}=4/3\right)$
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
$\mathrm{\pi}$
t is equation of oscillation of source S
_{1}
and y
_{2}
= 5 (mm) sin (
$\mathrm{\pi}$
t +
$\mathrm{\pi}$
/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 :-
$\left(1\right)\sqrt{2+\sqrt{3}}\mathrm{mm}$
(2)
$5\sqrt{3}/2$
mm
(3) 5 mm (4)
$5\sqrt{2}$
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
Shubhrajyoti Ghosh
Subject: Physics
, asked on 16/3/18
No links please
Q. State Huygen's principle. If white light is used in place of monochromatic light in Young's double slit experiment, what change will be observed in the interference pattern? What are the conditions for two sources being 'Coherent'?
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
No links please
Q. The interior of a hollow metal sphere is polished to serve as a mirror. At a point 12 cm from the centre of the sphere of radius 24 cm, a point source of light is placed. Locate its image formed by two successive reflections, the first reflection taking place at the (a) far wall (b) near wall.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
No links please
Q. An image produced by a concave mirror is one-fourth the size of the object. If the object is moved 10 cm towards the mirror, its image will be only half the size of the object. Calculate the focal length of the mirror.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
No links please
Q. The interior of a hollow metal sphere is polished to serve as a mirror. At a point 12 cm from the centre of the sphere of radius 24 cm, a point source of light is placed. Locate its image formed by two successive reflections, the first reflection taking place at the (a) far wall (b) near wall.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
A ray of light of wave length 6000
$\stackrel{o}{A}$
falls on a metal plate. To drag electron from the metal 1.77 ev energy is required.Find the maximum energy of the emitting electron and the threshold frequency of the metal. [Given Plank's constant 'h' = 6.6 x 10
^{-27}
erg-sec]
Answer
1
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What are you looking for?

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$\xb0$ on an air-glass interface gets reflected. The angle of deviation of the ray is

(a) 45$\xb0$

(b) 180$\xb0$

(c) 135$\xb0$

(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$\xb0$ (2) 30$\xb0$

(3) 45$\xb0$ (4) 60$\xb0$

(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 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})Q. If y

_{1}_{ }= 5 (mm) sin $\mathrm{\pi}$t is equation of oscillation of source S_{1}and y_{2}= 5 (mm) sin ($\mathrm{\pi}$ t + $\mathrm{\pi}$/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 :-$\left(1\right)\sqrt{2+\sqrt{3}}\mathrm{mm}$ (2) $5\sqrt{3}/2$mm

(3) 5 mm (4) $5\sqrt{2}$mm

^{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
- 60
- 70

4. 80^{o}^{o}^{o}^{o}please 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.

Q. State Huygen's principle. If white light is used in place of monochromatic light in Young's double slit experiment, what change will be observed in the interference pattern? What are the conditions for two sources being 'Coherent'?

Q. The interior of a hollow metal sphere is polished to serve as a mirror. At a point 12 cm from the centre of the sphere of radius 24 cm, a point source of light is placed. Locate its image formed by two successive reflections, the first reflection taking place at the (a) far wall (b) near wall.

Q. An image produced by a concave mirror is one-fourth the size of the object. If the object is moved 10 cm towards the mirror, its image will be only half the size of the object. Calculate the focal length of the mirror.

Q. The interior of a hollow metal sphere is polished to serve as a mirror. At a point 12 cm from the centre of the sphere of radius 24 cm, a point source of light is placed. Locate its image formed by two successive reflections, the first reflection taking place at the (a) far wall (b) near wall.

^{-27}erg-sec]