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What is Seebeck effect? Give one example.

Posted by Ishu Chauhan 8 years, 1 month ago

1 answers

phenomenon in which a temperature difference between two dissimilar electrical conductors or semiconductors produces a voltage difference between the two substances.

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Why transmission of TV signals via sky wave is not possible?

Posted by Surbhi Raghu 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Astha Srivastava 8 years, 1 month ago

when the frequency range is more than 40mhz then the ionosphere is totaly unable to reflect the signal back to the earth.as we know that the frequency range of TV signals is 100mhz-200mhz.so the transmission of TV signals via sky waves is not possible.

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The small ozone layer at the top of the stretosphere is crucial for human survival

Posted by Sachin Uniyal 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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Optical and radio telescopes are build at ground while x ray anatomy is only possible by orbitting the earth.

Posted by Sachin Uniyal 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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after downloading a pdf file i should get 18 sample papers but i got only 1 sample paper

Posted by Shivani Prajapat 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ankita Vats 8 years ago

You can buy......

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Why for ground wave transmission, size of antenna(d) should be comparable to wavelength(l) of signal, i.e. d=l/4.

Posted by Rishav Sharma 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Priya Prakash S 8 years, 1 month ago

For effective transmission.

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Describe the principal construction and working of cyclotron . explain why an electron cannot be accelerated using a cyclotron

Posted by Dabbang Pandey 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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What is the AC on a complete cycle?

Posted by Surbhi Raghu 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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Lens makers formula

Posted by Vaishnavi Keshari 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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What is the principle of potentiometer

Posted by Singh Monika 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Pranjali Mahajan 8 years, 1 month ago

V direct proportional to l

0Thank You

Yashvardhan Singh 8 years, 1 month ago

When a constant current pass through the potentiometer wire of uniform area of cross section the potential drop across any section of wire is directly proportional to the length of that portion.

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Juhi Ojha 8 years, 1 month ago

Zero deflection method or concept of potential gradient

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A capacitor has been charged by dc source . What are The magnitude of conduction and displacement current??

Posted by Piyush K 8 years, 1 month ago

CBSE > Class 12 > Physics

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Explain with the help of graph variation of conductivity with temperature of a metallic conductor

Posted by Juhi Ojha 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

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What is the electric flux through a cube of side 1cm which encloses an electric dipole?

Posted by Yashvardhan Singh 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yuthika Yadav 8 years, 1 month ago

Zero as net charge enclosed is zero

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Atom and nuclei important questions tell me

Posted by Abhinav Arya 8 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Surbhi Raghu 8 years, 1 month ago

Binding energy per nucleon vs mass no. curve ,

1Thank You

Priya Prakash S 8 years, 1 month ago

Radioactivity derivation

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Pranjali Mahajan 8 years, 1 month ago

Energy spectrum decays bas

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Nidhi Mishra 8 years, 1 month ago

pura hydrogen spectrum and nuclei me half life etc. ki derivation

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Why electric field lines become curved at the edges? Plzzz reply fasttt..

Posted by Shivam Sharma 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Nidhi Mishra 8 years, 1 month ago

with increase in distance there is repulsion b/w e.f lines .so the lines are not parellel but simply curves

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Dual nature of radiation ko kasa learn Kara or iska important topics kya h

Posted by Tanu Sharma Sharma 8 years, 1 month ago

CBSE > Class 12 > Physics

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Differnece between potential difference and emf

Posted by Bhavy Bhatia 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ishu Chouhan 8 years, 1 month ago

Potential difference is defined as amount of work done required to bring + ve charge from higher potential to lower potential . In contrast , emf is amount of work done required to bring + ve charge from lower to higher potential.

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What happens if dielectric constant is increased...... B/with two point charges

Posted by Aparna Nair 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Aparna Nair 8 years, 1 month ago

Decreases the force

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Is cylindrical and spherical capacitor in syllabus....

Posted by Himanshu Jain 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Garima Suyal 8 years, 1 month ago

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How wil the distance of closest approach be affected be when the kinetic energy of the a-particle is doubled

Posted by Anmol Kumar 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Prayag Shandilya 8 years, 1 month ago

It will become half as it is inversely proportional to kinetic energy

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Capacitor when connected to battery and disconnected from battery

Posted by Prikshit Kundu 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ankita Vats 8 years ago

?????

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How does this happen when we open the switch,the current go very far in a short span of time

Posted by Rishav Yadav 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Prayag Shandilya 8 years, 1 month ago

This is because the conductor or the wire through which we are passing current is full of electrons the electrons get drifted and a force acts on all electrons and hence current flows

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Necessary condition for total internal reflection (TIR)

Posted by Rishav Yadav 8 years, 1 month ago

CBSE > Class 12 > Physics