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Given the electric feild in the region E=2xi^, find the net electric flux through the cube and the charge enclosed by it

Posted by Gur Simran Singh 7 years ago

CBSE > Class 12 > Physics

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prove mathmatically that the average value of AC over one complete cycle is zero

Posted by Aditya Gupta 7 years ago

CBSE > Class 12 > Physics

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State which of two the capacitor or an inductor tends to becomes a short when the frequency of the applied alternating voltage has a very high value

Posted by Brijesh Yadav 7 years ago

CBSE > Class 12 > Physics

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ncert example9. 8

Posted by Aafia Bushra 7 years ago

CBSE > Class 12 > Physics

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A photosensitive surface emit photoelectron when red light falls on it will the surface emit photoelectron when blue light will fall on it . give reason

Posted by Lucky' Ch. 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 7 years ago

photoemission takes place when red light is incident means hc/λred>Work function..1 When blue colour light is incident then energy imparted to the electron is E=hc/λblue as λred>λblue so hcλblue>hcλred...2 from relation 1 and 2 hc/λblue>W so photoelectron will be emitted when blue light is incident .Regards

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What is binding energy ?

Posted by Gagandeep Rathi 7 years ago

CBSE > Class 12 > Physics

2 answers

Yogita Ingle 7 years ago

The energy that is necessary to split the nucleus of an atom into its components namely: neutrons and protons or collectively known as the nucleons. The binding energy of nuclei is a positive value because every nuclei need net energy to isolate them into every neutron and proton.

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Abdul Rafique 7 years ago

It is that energy which can hold the nucleus together

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Name the current which flows in the absence of electric charge

Posted by Rahil Hasan 7 years ago

CBSE > Class 12 > Physics

1 answers

Aditya Sanganal 7 years ago

Displacement current

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Why cannot we take one slab of p-type semiconductor and physically join it to another slab of n-type semiconductor to get p-n junction?

Posted by Arshad Ali 7 years ago

CBSE > Class 12 > Physics

1 answers

Sanjay Singh 7 years ago

See ncert example

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Important question for board exams

Posted by Aanchal Goyal 7 years ago

CBSE > Class 12 > Physics

3 answers

Aanchal Goyal 7 years ago

Ok i understand i m very thanking to you

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Mansi Sharma 7 years ago

But some questions from sample paper tooo ...

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Nitika Neb 7 years ago

You should refer to ten year papers

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What are the limitations of nuclear chain reaction

Posted by Ayushi Patel 7 years ago

CBSE > Class 12 > Physics

1 answers

Sanjay Singh 7 years ago

Very large area is reqired.. Chances of accidents

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Why a rheostat is connected in series with battery in potentiometer experiment?

Posted by Rajat Dhull 7 years ago

CBSE > Class 12 > Physics

2 answers

Yuvraj Sharma 7 years ago

Sorry this is for resistance box

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Yuvraj Sharma 7 years ago

For control on deflection of galvanometer needle

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In potentiometers Why should the emf of required voltage is less than than external voltage?

Posted by Vikji Rawat 7 years ago

CBSE > Class 12 > Physics

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What factor wave depend.,

Posted by Shubhanker Kumar 7 years ago

CBSE > Class 12 > Physics

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How are electromagnetic waves generated ??

Posted by Harshit Rathi 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitin Yadav 7 years ago

By accelerating a charged particle or by varying electric and magnetic fields

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What is polroids

Posted by Nikki Khiojh 7 years ago

CBSE > Class 12 > Physics

1 answers

Gaurav Seth 7 years ago

Polaroids are polarizing materials consisting of long chain of molecules aligned in a particular direction.
Polaroid’s are in the form of thin sheets.
Every Polaroid has pass axis. Pass axis is like a gate of aPolaroid which determines how the light will pass through it.
There is horizontal as well as vertical pass axis.
Unpolarized light on passing through a Polaroidit gets polarized.

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Formula of all chapters

Posted by Ganeshan Chavan 5 years, 8 months ago

CBSE > Class 12 > Physics

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Define Quality Factor of resonance in series LCR circuit . What is its SI unit ?

Posted by Arti Vishwakarma 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 7 years ago

Quality factor is defined as the ratio of voltage across inductor or capacitor to the voltage across resistor at resonance

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. Two charges q and – 3q are placed on x-axis separated by distance d. Where a third charge 2q should be placed such that it will not experience any force ?

Posted by Chesta Jain 7 years ago

CBSE > Class 12 > Physics

1 answers

Shubham Sharma 7 years ago

D/√3

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Half life of certain radioactive nuclide is 3 days. It's activity is 8 times the safe limit. After how much time will the activity of radioactive sample reach the safe ĺimt

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

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What is the ratio of nuclear density of two nuclide having mass no in the ratio 1:4

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

1 answers

Shubham Sharma 7 years ago

1:1

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The half life of radioactive element 'A'is same as the mean life time of 'B' , instantly both have same number of atoms. 'B'decays faster þ than 'A'. Why?

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

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Which book or sample paper is best for the good preparation to get excellent marks

Posted by Harshit Pratap Singh 7 years ago

CBSE > Class 12 > Physics

3 answers

Vijay Pandit 7 years ago

Oswal is the one of the best option for the good preparation

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Aditya Ashutosh 7 years ago

Oswaal is best

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Bhavya Chugh 7 years ago

Physics book by rachna sagar

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expression of capacitance of a parallel plate capacitor when a dielectric slab is placed between the plates of capacitor.

Posted by Nitika Neb 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitin Yadav 7 years ago

C=KE.A/d

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Numerical electromagnetic waves

Posted by Shikha Shikha 7 years ago

CBSE > Class 12 > Physics

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Anyone has physics question paper? i have exam on 4 dec....plz help????

Posted by Nitish Sharma 7 years ago

CBSE > Class 12 > Physics

2 answers

Nitish Sharma 7 years ago

Can u send it on Facebook plz???

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Punit Yadav 7 years ago

Ya i have

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What is the energy possessed by an electron whose principal quantum number is infinite

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 7 years ago

When n is infinity then energy is known is ionisation energy . with an increase in n the energy also increases .So if n is infinity so energy is also infinity

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Define ionisation energy

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitish Sharma 7 years ago

Min.energy required to remove an electron from the outermost shell of an atom.??

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Define ionisation potential

Posted by Aishwarya Hariharan 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 7 years ago

It is the amount of energy required by to knock an electron from ground state of an atom to completely out of an atom

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What is plane polarised light?

Posted by ????? ???? 7 years ago

CBSE > Class 12 > Physics

1 answers

Nitika Neb 7 years ago

A light wave that can vibrate in more than one medium is known as an unpolarized light The light which can vibrate only in single medium is known as a polarized light

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What is unpolarised light?

Posted by ????? ???? 7 years ago

CBSE > Class 12 > Physics