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Sudhanshu Singh
Subject: Physics
, asked on 11/4/18
Solve this
1. An observer is moving with half the speed of
light towards a stationary microwave source
emitting waves at frequency 10 GHz. What is the
frequency of the microwave measured by the
observer? (speed of light = 3 x 10
8
ms
-l
)
(a) 12.1 GHz (b) 17.3 GHz
(c) 15.3 GHz (d) 10.1 GHz
Answer
1
Hrushikesh Badgujar
Subject: Physics
, asked on 1/4/18
Two organ pipes ,each closed at one end ,gives 5 beats per sec,when emitting their fundamental notes.If their lengths are in ratio of 50:51 their fundamental frequencies (in Hz) are
Answer
1
Hrushikesh Badgujar
Subject: Physics
, asked on 1/4/18
How fast one must move to see a red light signal as a green one?Given Ir=6200A and Ig=5400A
Answer
1
Aparna Sahu
Subject: Physics
, asked on 27/3/18
Solve this.
Answer
1
Shri Ganesh
Subject: Physics
, asked on 25/3/18
please help me solve this questions.
Q.22. Three blocks A, B and C are kept as shown in figure. The coefficient of friction between A and B is 0.2, B and C is 0.1, C and ground is 0.0. The mass of A, B and C are 3 kg, 2 kg and 1 kg respectively. A is given a horizontal velocity 10 m/s. A, B and C always remain in contact i.e. lies as in figure. The total work done by friction will be
(a) - 75 J
(b) 75 J
(c) - 150 J
(d) - 100 J
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 16/3/18
No links please
Q.2. State Einstein's equation and explain it. Find momentum when wavelength is 1
A
o
.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
No links please
Q13. What is meant by de Broglie wavelength. Some how the de Broglie wavelength associated with a moving particle changed from 0.2 Å to 0.4 Å. Determine the change in momentum of the particle. [h = 6.63 × 10
–34
Js ]
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
Q. State the laws of photoelectricity. Find the wavelength of X-ray when applied voltage is X-ray tube is 10,000 volts.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
Q. If the wave length is 2000 Å falls on a plate (metal) it is positively charged but it the wave length is 3400 Å there is no change of the electrical state of the plate - explain.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
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
Prateek Walia
Subject: Physics
, asked on 8/3/18
Ans to this ques please
Q. A symmetric biconvex lens of radius of curvature R and made of glass of refractive index 1.5, is placed on a layer of liquid placed on top of a plane mirror as shown in the figure. An optical needle with its tip on the principal axis of the lens is moved along the axis until its real, inverted image coincides with the needle itself. The distance of the needle from the lens is measured to be x. On removing the liquid layer and repeating the experiment, the distance is found to be y. Obtain the expression for the refractive index of the liquid in terms of x and y.
Answer
1
Prerna Varshney
Subject: Physics
, asked on 6/3/18
Q.Explain two features to distinguish between the interference pattern in Young's double slit experiment with the diffraction pattern obtained due to a single slit.
Q. A monochromatic light of wavelength 500 nm is incident normally on a single
slit of width 0.2 mm to produce a diffraction pattern. Find the angular width of the central maximum obtained on the screen.
Estimate the number of fringes obtained in Young's double slit experiment with
fringe width 0.5 mm, which can be accommodated within the region of total
angular spread of the central maximum due to single slit.
Answer
1
Deepak Vyas
Subject: Physics
, asked on 6/3/18
Q9 part b
Q9(b). In Young's double slit experiment, the two parallel slits are made 1mm apart and a screen is placed 1 m away. What is the fringe separation when blue green light of wavelength 500 nm is used.
Answer
2
Deepak Vyas
Subject: Physics
, asked on 6/3/18
Solve this:-
4. The ratio of the widths of two slits in Young's double slit experiment 4:1. Evaluate the ratio of the intensities at maxima and minima in the intererference pattern.
7. The radius of curvature of each face of biconvex lens, made of glass of refractive index 1.5 is 30 cm. Calculate the focal length of the lens in the air.
9 (b) In Young's double slit experiment, the two parallel slits are made 1 mm apart and a screen is placed 1 m away. What is the fringe separation when blue green light of wavelength 500 mm is used.
Answer
1
Kurian J
Subject: Physics
, asked on 6/3/18
prove that the width of te central maximum is twice that of the secondary maximum ???
Answer
1
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Next
What are you looking for?
1. An observer is moving with half the speed of
light towards a stationary microwave source
emitting waves at frequency 10 GHz. What is the
frequency of the microwave measured by the
observer? (speed of light = 3 x 108 ms-l)
(a) 12.1 GHz (b) 17.3 GHz
(c) 15.3 GHz (d) 10.1 GHz
Q.22. Three blocks A, B and C are kept as shown in figure. The coefficient of friction between A and B is 0.2, B and C is 0.1, C and ground is 0.0. The mass of A, B and C are 3 kg, 2 kg and 1 kg respectively. A is given a horizontal velocity 10 m/s. A, B and C always remain in contact i.e. lies as in figure. The total work done by friction will be
(a) - 75 J
(b) 75 J
(c) - 150 J
(d) - 100 J
Q.2. State Einstein's equation and explain it. Find momentum when wavelength is 1 .
Q13. What is meant by de Broglie wavelength. Some how the de Broglie wavelength associated with a moving particle changed from 0.2 Å to 0.4 Å. Determine the change in momentum of the particle. [h = 6.63 × 10–34Js ]
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. A symmetric biconvex lens of radius of curvature R and made of glass of refractive index 1.5, is placed on a layer of liquid placed on top of a plane mirror as shown in the figure. An optical needle with its tip on the principal axis of the lens is moved along the axis until its real, inverted image coincides with the needle itself. The distance of the needle from the lens is measured to be x. On removing the liquid layer and repeating the experiment, the distance is found to be y. Obtain the expression for the refractive index of the liquid in terms of x and y.
Q. A monochromatic light of wavelength 500 nm is incident normally on a single
slit of width 0.2 mm to produce a diffraction pattern. Find the angular width of the central maximum obtained on the screen.
Estimate the number of fringes obtained in Young's double slit experiment with
fringe width 0.5 mm, which can be accommodated within the region of total
angular spread of the central maximum due to single slit.
Q9(b). In Young's double slit experiment, the two parallel slits are made 1mm apart and a screen is placed 1 m away. What is the fringe separation when blue green light of wavelength 500 nm is used.
4. The ratio of the widths of two slits in Young's double slit experiment 4:1. Evaluate the ratio of the intensities at maxima and minima in the intererference pattern.
7. The radius of curvature of each face of biconvex lens, made of glass of refractive index 1.5 is 30 cm. Calculate the focal length of the lens in the air.
9 (b) In Young's double slit experiment, the two parallel slits are made 1 mm apart and a screen is placed 1 m away. What is the fringe separation when blue green light of wavelength 500 mm is used.