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Why the short, straight interference fringes observed in YDSE are actually hyperbolic in shape?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is flint glass prisms?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Riya Rana 6 years, 1 month ago

It is used as telescope lenses. It has larger refractive index hence, more refration and less speed of light (in medium).

1Thank You

ANSWER

What is coefficient of coupling? Write the significance of mutual inductance if the coefficient of coupling lies between 0 and 1.

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How will you wind a resistance coiso that its self induction is minimum?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Mahi D 6 years, 1 month ago

To make non-inductive coils, resistance coils are made of doubled up insulated wires. They are double wound so that the currents in the two wires flow in opposite directions and so create equal and opposite magnetic fields which cancel each other and so inductive effect is reduced.

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ANSWER

If it is possible to convert a 3D wave into a 2D wave, then why it is not possible to convert a 1D wave into 2D wave?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Achyut Singh 6 years, 1 month ago

Whats a 3d wave .?? Unable to understand. Aren't you from NASA. ?

1Thank You

ANSWER

Why the frequency remain unchanged of a refracted wave?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Tamanna Sharma 6 years, 1 month ago

Aditya any mahi both of you tell me about energy and wavelength, but I want ans as frequency consideration not other factors

0Thank You

Mahi D 6 years, 1 month ago

Maybe the reason that frequency is not changing from one medium to another is that energy of light is same in both the mediums so frequency is also unaffected...

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Tamanna Sharma 6 years, 1 month ago

You say," from one medium to another frequency never changes".why?.????

1Thank You

Aditya Chauhan 6 years, 1 month ago

Although the wave slows down, its frequency remains the same, due to the fact that its wavelength is shorter. When waves travel from one medium to another the frequency never changes. As waves travel into the denser medium, they slow down and wavelength decreases.

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ANSWER

Bohr's postulate

Posted by Anjali Dubey 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

First Postulate:Atoms have some specific stable energy states(called stationary states) where electrons could orbit around the nucleus without emitting radiation
Second Postulate: Orbiting of electrons occur only in the orbits (called stable orbits) where electrons’ angular momentum(L) is equal to the integral multiples ofh/(2π), leading to the quantization of moving electron
Third Postulate: Electron while jumping from higher(initial) energy state to lower(final) energy state, emit a photon of energy equal to the energy difference between the 2 energy states, and its frequency is given by:
hv = E_i - E_f

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Why only transverse wave can be pilarised?

Posted by Deepak Kumar 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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If the two adjacent walls of a room and the ceiling is a plane mirror and a object is placed in the center of the room then, how many images fomed by these mirrors?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

5 answers

Tamanna Sharma 6 years, 1 month ago

Koi to solve kar do yrr.???

0Thank You

Tamanna Sharma 6 years, 1 month ago

Infinite kehne se kam nahi chalega kya tumne problem literally solve kiya,Aditya

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Tamanna Sharma 6 years, 1 month ago

Are you trying to solve it

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Tamanna Sharma 6 years, 1 month ago

I know the only answer (7) of this question as given in answer key but how, I don't know,l have no key points for image formation by 3 perpendicular mirror,only know image formation by 2 mirrors,I tried to solve it by taking 2 mirrors at 1 time but then the image overlapping case was too much and totally confused me. So, please try to solve it at once.

1Thank You

Aditya Chauhan 6 years, 1 month ago

??lrts try it i think infinite

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Why only transverse waves can be polarized?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Rain Drop 6 years, 1 month ago

The reason that only transverse waves can be polarised is that their vibrations can potentially occur in all directions perpendicular to the direction of travel. It is therefore possible to confine the vibrations to a single plane.

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Shruti Gupta 6 years, 1 month ago

Bcz longtitudnal waves are already polarised

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How does the metal detector at the airports work?

Posted by Medha Bhatt 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Tamanna Sharma 6 years, 1 month ago

This is simply based on the PI principle, its a setup of transmitting pulse (small magnetic field) and detection of these pulse. If any metallic object is placed in this it create a field in opposite direction and detecter can detect the metallic object

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In young's double slit experiment if I consider these 2 slits individually 1 by1, now 1slit can perform diffraction of light and similarly other one also ,Now my question is, this phenomenon happen from the slits shows diffraction (means intensity goes on decreasing)but compose this setup as YDSE intensity distribution is uniform ( means no brightest central maxima and no further lower maxima is observed)

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Prove using bohr's theory that an atom behaves like a magnetic dipole.

Posted by Mahi D 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Mahi D 6 years, 1 month ago

But in question it is given to prove this using bohr 's theory.. please answer using it in derivation..

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Tamanna Sharma 6 years, 1 month ago

As electrons revolve around the nucleus and behaves like a electron loop and the current flows in opposite direction to the electron ,hence the upper and lower faces of electron loop behaves as poles of magnet and have a definite dipole moment .Hence atoms behave like a magnetic dipole.

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ANSWER

Charge q1=+6.0 nC is on y axis at y=+3cm and charge q2=-6.0 nC is on y axis at y=-3cm.Calculate the force on a test charge q not =2 nC placed on x axis at x=4cm.

Posted by Abhishek Kishan 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Medha Bhatt 6 years, 1 month ago

Force experienced by the charge qnot will be equal to 4.32*10^-9 N

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Tamanna Sharma 6 years, 1 month ago

61N

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The electric force between two charged particle situated at a given distance is F newton .what will be the force if the distance us made half

Posted by Sabu Joseph 6 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Tamanna Sharma 6 years, 1 month ago

Medha it's inverse square law ,distance becomes half the force becomes 4times

1Thank You

Medha Bhatt 6 years, 1 month ago

The force becomes 1/4th of the original force

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Tamanna Sharma 6 years, 1 month ago

So simple, the force becomes 4 times

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ANSWER

Torque on a current loop is............. when placed along the magnetic field lines.

Posted by Krish Batoye 6 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Sudhanshu Shekhar 6 years, 1 month ago

Torque=0 ,since angle between magnetic dilole and magnetic field vector zero so costheta 0

0Thank You

Mahi D 6 years, 1 month ago

Torque is MAXIMUM. Because angle b/w normal to plane of coil and magnetic field is 90°

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Arti Yadav 6 years, 1 month ago

Loop is....

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What is modern physics ....which chapter comes under this!

Posted by Abhisektiwary 3676 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Tamanna Sharma 6 years, 1 month ago

It's an adavnce discription of newly experimental theories. 1. Dual nature 2. Atoms and nuclei 3. Electronic devices 4. Communication systems ( not in syllabus but some concepts directly used in EM waves so it's better to go through this chapter at least once. ) I hope this will help you 1??

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ANSWER

Why there is no arrangement of energy storage in a resistor unlike a capacitor and a inductor?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Achyut Singh 6 years, 1 month ago

The function of resistance is to emitt energy in the form of heat.

1Thank You

Yogita Ingle 6 years, 1 month ago

A capacitor stores electrons as static charge, an inductor as a magnetic field.
A resistor is a plain passive device.

If you think of electricity as water, a capacitor is like a rubber membrane across a pipe, an inductor is like an axial turbine (water makes it spin, it continues to spin and pump water a while after the flow has stopped), resistor is just like a pipe whose dimensions determine the rate of water flow.

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How a stepdown transformer is used for welding purposes?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

For jointing two metallic joints through welding process, high temperature is required. The temperature is proprtional to the square of the current through the circuit.

The higher the current, the higher the temperature.

When the secondary of the transformer has less number of turns in comparison to the number of turns in the primary, it is called a step down transformer.

The secondary voltage of step down transformer is less than the primary and the current of the secondary is more than the primary current. Principally, the power of the primary and secondary is equal.

This larger secondary current is very useful in welding process. That is why step down transformer is used for welding

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How speedometer make use of eddy current to the inst. speed of vechile?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Aditya Chauhan 6 years, 1 month ago

In a speedometer, a magnet rotates according to the speed of the vehicle. The magnet rotates inside an aluminium cylinder (drum) which is held in position with the help of hair springs. Eddy currents are produced in the drum due to the rotation of the magnet and it opposes the motion of the rotating magne

2Thank You

ANSWER

Can someone from Kendriya Vidyalaya post their sample paper please? Thank you!

Posted by Becky Shoshannah 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Shruti Gupta 6 years, 1 month ago

Kv yet not posted their seperate sample papers

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Kyaa board sample paper and board paper format wise and mark distribution of each chapter same rahenge kyaa??

Posted by Tushar Jaihal 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Nitish Singh 6 years, 1 month ago

Yes

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Which is more dangerous AC or DC, I think it's DC because I read it somewhere but in some books it says AC.please clear this confusion.

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

5 answers

Abhishek Sah 6 years, 1 month ago

AC is more dangerous than DC , As both gives electric shock but AC have attractive force but DC have repulsive force.so,..

2Thank You

Aditya Chauhan 6 years, 1 month ago

Your welcome

2Thank You

Tamanna Sharma 6 years, 1 month ago

Thanks both of you for this amazing explation

3Thank You

Aditya Chauhan 6 years, 1 month ago

Both you can touch it and then i will also come to know sorry just kidding ... ..... ................Right answer is One of the reasons that AC might be considered more dangerous is that it arguably has more ways of getting into your body. Since the voltage alternates, it can cause current to enter and exit your body even without a closed loop, since your body (and what ground it's attached to) has capacitance. DC cannot do that.

3Thank You

Arpit Pathak 6 years, 1 month ago

Hey tamanna ! According to Charles Dalziel experiments on men and women, muscles contraction is continuous in case of an electric shock with DC current. Whereas in the case of AC current, a person experiencing electric shock undergoes a series of muscle contraction. Series of muscle contraction causes very severe damage to the muscles. Due to the capacitive behaviour of the skin coming in contact with the current carrying conductor, more current can pass through the body if the voltage is rapidly changing. Studies have shown that twofold of increase in the voltage increases sevenfold increase in the current. DC current “let-go” threshold is higher than the AC “let-go” threshold. More DC current is required to produce a similar effect as of AC current.

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Can we decrease the speed of light?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Aditya Chauhan 6 years, 1 month ago

??Scientists have long known that the speed of light can be slowed slightly as it travels through materials such as water or glass. However, it has generally been thought impossible for particles of light, known as photons, to be slowed as they travel through free space, unimpeded by interactions with any materials.

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How we can create a positron?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Aditya Chauhan 6 years, 1 month ago

I dont know much about it but .... Positrons are emitted in the positive beta decay of proton-rich (neutron-deficient) radioactive nuclei and are formed in pair production, in which the energy of a gamma ray in the field of a nucleus is converted into an electron-positron pair

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ANSWER

Yrr fringe width ke numerical nahi ban rahe,koi suggestion do,wave optics nahi ho pa rha he.

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics