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Application of gauss theorem in calculation of electric field

Posted by Anshu Bhardwaj 6 years, 11 months ago

1 answers

Yogita Ingle 6 years, 11 months ago

Gauss’s Law can be used to solve complex electrostatic problems involving unique symmetries like cylindrical, spherical or planar symmetry. Also, there are some cases in which calculation of electric field is quite complex and involves tough integration. Gauss’s Law can be used to simplify evaluation of electric field in a simple way.

We apply Gauss’s Law in following way:

Choose a Gaussian surface, such that evaluation of electric field becomes easy
Make use of symmetry to make problems easier
Remember, it is not necessary that Gaussian surface to coincide with real surface that is, it can be inside or outside the Gaussian surface

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Total internal reflection

Posted by Abhishek Yadav 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Kumar 6 years, 11 months ago

Condition for TIR 1. Light always passes from denser to rarer. 2. Angle of incidence is always greater than anhle of crictical angle Sin ic =1/u

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Find speed of electrob in 3rd orbit of he^+ ion

Posted by Abhinandan Phutela 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

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What focal length should be reading spectacles have for person for whom the least distance of distinct vision is 50 cm

Posted by Rahul Kumar 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Sangje Lamo 6 years, 11 months ago

Here V=-50 cm U=-25 cm By using lens formula, we get F=-6. 25 cm

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Name the charge carriers of electric current in Silver fail

Posted by Vivek Rawat 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Shaily Chauhan 6 years, 11 months ago

ions

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2 identical metal sphere having charge +4C & -10C are kept at certain distance. If 3rd uncharged identical sphere C is placed in contact with A and removed & then in contact with B & removed. Sphere A & B are brought in contact. Find charge on each sphere.

Posted by Prachi Saini 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Kumar 6 years, 11 months ago

When C contact with A charge become q+0/2= q/2 on each sphere therefore charge on A beckmw q/2. When charge sphere C(q/2) contact with B charge become on each is q/2+q= 3q/2 ÷ by 2= 3q/4. Due to which charge on B become 3q/4.

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Is circular current loop as a magnetic dipole is in syllabus?

Posted by Saumya Agrawal 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Sangje Lamo 6 years, 11 months ago

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Prachi Saini 6 years, 11 months ago

Yes it is

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What are the necessary things to do for getting 95+marks can i prefers previous years question paper how much question in a paper are same as previous years

Posted by Gaurav Nainwal 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Mansi Sharma 6 years, 11 months ago

I think 30% que' or may be it is 40% but we need to study the whole theory derivations and numericals!!!

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What is Quantum Realm?

Posted by Gautãm . 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

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SI unit of mobility?

Posted by Nisha Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Kiley Jenner 6 years, 11 months ago

Coulomb sec/m

2Thank You

Gaurav Seth 6 years, 11 months ago

Electron Mobility(μ) is defined as the drift velocity of the electrons(in a current carrying conductor) per unit electric field.In order to workout the units note that the unit of drift speed(vd) is (ms-1) and that of electric field is(Volt/m = V/m).Thus the unit of mobility is (ms-1/Vm-1), which is m2/Vs .

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Why does steady current not flow in a capacitor connected across a battery ?

Posted by Sanjay Dahiya 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Surabhi Tiwari 6 years, 11 months ago

In the steady state no current flows through capacitor because, we have two sources( battery and fully chrged capacitor) of equal potential connected in opposition .

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Is atom an electric dipole

Posted by Krishnendu S K 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Kalas Sahu 6 years, 11 months ago

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What is an impedsnce

Posted by Yash Rajput 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Akarsh Kumar 6 years, 11 months ago

It has same physical meaning as resistance in an LCR circuit

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What is the importance of a radical magnetic field and how is it produced?

Posted by Bikram Ralh 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Rohit Kumar 6 years, 11 months ago

In one sentence. It increase the torque circular coil in galvanometer.

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Nitika Neb 6 years, 11 months ago

Magnetic properties of free radicals. The magnetic properties of free radicals provide a powerful tool for their detection and study. ... Free radicals, however, are paramagnetic (attracted by a magnet) because of the spin of the odd electron, the spins of the remaining paired electrons effectively canceling each other.

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Defined mobility

Posted by Khushi Gupta 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Nitika Neb 6 years, 11 months ago

It is the ratio ofwith electric field

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Saumya Agrawal 6 years, 11 months ago

Drift velocity attained per unit electric field....

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Why the binding energy of daughter nucleus per nucleon is more than that of parent nucleus

Posted by Anshika Kaushik 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Somya Duhan 6 years, 11 months ago

As parent nucleus was unstable so BE per nucleon less and does fission . Then the daughter nucleus should be stable and of high BE per nucleon. Perhaps be the answer.

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Introduction of capacitance

Posted by Ankit Patidar 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 6 years, 11 months ago

Capacitance is the ratio of the change in an electric charge in a system to the corresponding change in its electric potential. ... The SI unit of capacitance is the farad (symbol: F), named after the English physicist Michael Faraday. SI unit:farad Other units:μF, nF, pF

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Write three characteristics features of Photoelectric effect which cannot be explained on the basis of wave theory

Posted by Baldev Prajapati 6 years, 11 months ago

CBSE > Class 12 > Physics

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Sky wave propagation

Posted by Ramesh Yadav 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 11 months ago

Sky wave propagation is a mode of wave propagation in which the radiowaves emitted from the transmitter antenna reach the receiving antenna after reflection by the ionosphere.
In sky wave propagation, the frequency of radio waves range from 1710 kHz to 40 MHz.
This mode of propagation is used by short wave broadcast service.

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How to prepare 1 or 2 marks questions for physics

Posted by Satyam Verma 6 years, 11 months ago

CBSE > Class 12 > Physics

3 answers

Navya Singh 6 years, 11 months ago

See sample paper nd 10 years ...also arihant

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Saurabh Yadav 6 years, 11 months ago

Bro just make clear u know the deep concepts and formulas of each chapter and do practice derivations and you are all set to tackle the problems . Hope u got it.

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Rupas Chettri 6 years, 11 months ago

See imoprtant qution in this app bro

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Why current is not a vector quantity

Posted by Rupas Chettri 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Shama Shama Sheikh 6 years, 11 months ago

Because current does not follow law of vector addition

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Nitika Neb 6 years, 11 months ago

electric current should be considered a vector as it has both magnitude and direction. But in addition, vectors obey the law of parrellogram of vectors, which the electric current does not obey. For this reason, current is a scalar quantity and not a vector.

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Explain refractive index, critical angle.

Posted by Srishailam . 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 11 months ago

Critical angle : When a light ray travelling from optically denser medium(high refractive index) to optically rarer medium(low refractive index) it undergoes refraction. Due to this, for a given angle of incidence at interface of two medium, light ray deviates its path in rarer medium away from normal. If we keep on increase the angle of incidence, at particular angle of incidence the light ray passes over the surface of denser medium giving an angle of refraction that equals 90º. This angle of incidence for which we get angle of refraction at rarer medium equals 90º is known as critical angle. If the angle of incidence exceeds this critical angle, there will not be any refraction and total internal reflection is taking place.
Refractive Index: A ray of light changes its direction when it enters from one medium to another medium. This happens because speed of light is different in different media. For example; the speed of light is 3 x 10⁸ m/s (2.99x10⁸ m/s) in vacuum and it is 2.98 x 10⁸ m/s in air. Refractive Index is the extent of change of direction of light in a given pair of media. The refractive index is a relative value of speed of light in the given pair of media. Thus, to calculate the refractive Index the speed of light in two media is taken.

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The mass of Hydrogen atom is less than the sum of the mass of a proton an electron why is this ?

Posted by Anurag Vetma 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Mohit ..... 6 years, 11 months ago

E=mc^2 Energy released in the form of mass when proton and electron combines to form hydogen atom

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Saumya Agrawal 6 years, 11 months ago

Due to mass defect ....... i think

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An eletron and proton have the same de bringli wavelength which one posse more k.e energy

Posted by Durgeshwari Nahrel 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Bipin Joshi 6 years, 11 months ago

Electrom

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Somya Duhan 6 years, 11 months ago

De broglie wavelength =h/p And KE=p/2m means as p same so E is inversely with mass. Electron has more KE.

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What is standard resistance?

Posted by Nisha Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Rajan Baghel 6 years, 11 months ago

Standard resistance means internal resistance

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Ramesh Yadav 6 years, 11 months ago

What is standard resistance

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plzz...tell numericals kitne no. k aate h...phy..mein?

Posted by Nisha Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Rajan Baghel 6 years, 11 months ago

Yes 13 to15 marks

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Aryan Rai 6 years, 11 months ago

Max. 15 marks

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Distinguish between absolute anad relative refractive index of the medium

Posted by Nikhil Jaiswal 4 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Sia ? 4 years, 6 months ago

Relative refractive index : Relative refractive index is the ratio of the speed of light in the medium 1 to the speed of light in medium The value of absolute refractive index may be greater than or less than unity.
Absolute Refractive Index : Absolute refractive index is the ratio of the speed of light in vaccum to the speed of light in the medium. The value of absolute refractive index is greater than unity.

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Define ionization energy

Posted by Rajan Baghel 6 years, 11 months ago

CBSE > Class 12 > Physics