CBSE > Class 12 > Physics | CBSE Board | Homework Help

When we increase the reverse voltage across the pn junction ,the electric field across the diode junction increases (both external and internal )this results in the force of attraction on - ve charged electrons at junction this force frees electrons from their covalent bond and move them to the conduction band .when the electric field increases (with applied voltage) more and more electrons are freed from their covalent bond. this result in drifting of electrons across the junction and electron hole recombination occurs so a net current is developed and it increases rapidly with increase in electric field.

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Arisha Ashraf 6 years, 4 months ago

Breakdown of a diode occurs during its reverse biased condition and in reverse biased condition the +ve terminal of battery is connected to n side and the -ve one is to the p side . If we. Keep on increasing the applied reverse voltage ,the depletion width will increase accordingly. At a point which we can call as breakdown point. the diode will get damaged .at this point ,the diode behave more like a shorted wire and the internal resistance at this stage is approximately zero .according toOhm'slaw V=I/R and since resistance is very very low so current increases.

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What is bohr magneton?

Posted by Anuradha Chhonkar 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Arpita Sharma 6 years, 4 months ago

Bohr magneton is the unit of dipole moment

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ANSWER

Oswaal class12 question bank me kitne sample paper h

Posted by Kajal Kunwar 6 years, 4 months ago

CBSE > Class 12 > Physics

4 answers

Kajal Kunwar 6 years, 3 months ago

Okk

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Ron Vineetahuja 6 years, 4 months ago

5 sets

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Naaz Khan 6 years, 4 months ago

3 set h

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Kajal Kunwar 6 years, 4 months ago

Jaldi plzzz

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Show that velocity of electron in outer orbits are less than in inner orbits.

Posted by Sukhpreet Kaur 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Ron Vineetahuja 6 years, 4 months ago

Because outer electron is less tightly held by nucleus as compared to inner electron

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is All questions from NCERT text book for board exam 2020

Posted by Rani Kumari 6 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Vikas Semwal 6 years, 4 months ago

Yes for chemistry only... For math daubt

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Anuradha Chhonkar 6 years, 4 months ago

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ANSWER

In displacement method distance between two pins is greater than four times of focal length of lens. Why?

Posted by Raman Gupta 6 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Why electric field lines does not form closed loops

Posted by Shivam Wadhwa 6 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Aaditya Tyagi 6 years, 4 months ago

Electric field line starts from positive end and end to negative charge therefore not forming closed loop

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Sudhanshu Filmy World Dubey 6 years, 4 months ago

The electric field lines are start from positive to negative charge, lf there is only positive charge then electric field line start from charge and end at infinite, so that electric field line does not form closed loop.

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The blue colour gradually disappear when iron bars are added to the aqueous solution of CuSo4? Why?

Posted by Naaz Khan 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Arpita Sharma 6 years, 4 months ago

Because iron is more reactive than copper (see in electro chemical series) so iron easily displaces the copper from the solution...

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Best condector

Posted by Harpati Painkra 6 years, 4 months ago

CBSE > Class 12 > Physics

3 answers

Manish Kumar 6 years, 4 months ago

Silver

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Raghav Patidar 6 years, 4 months ago

Silver (Ag)

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Sudhanshu Filmy World Dubey 6 years, 4 months ago

In which charge are easily flow.ex, iron. .

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Draw the pattern of electric field lines when a electroc charge -Q is kept near the uncharged conducting plate

Posted by Krishna Khatik 6 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

A direct current of 2A and an alternating current having a maximum value of 2A flow through two idenrical resistence .what is the ratio of heat produced in two resistence ?

Posted by Ritesh Gupta 6 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

two charges of value 2 microcoulomb and -50 microcoulombs are placed it is apart calculate the distance of the point from the smaller charge where the intensity is zero

Posted by Tanu Choudhary 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Deeya Singh 6 years, 4 months ago

What is the distance between the two charges?

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ANSWER

What is main in emi

Posted by King Manan Jain 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Saurabh Singh 6 years, 4 months ago

self and mutual induction,eddy current and its application,energy stored in inductor,lenz law

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Y is ammeter connected in series and voltmeter in parallel connection

Posted by Najma Shaheen 6 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Gaurav Seth 6 years, 4 months ago

(i) The internal resistance of the ammeter is very low.If we connect it in series, then
the maximum current can flow through it. So the accurate current should be
measured. If we connect it in parallel then the accurate current can’t be
measured.

(ii) The internal resistance of the volt meter is very high and it is used to measure the
potential difference between the two points. If we connect it in series, then
there is no flow of current in the circuit because of high resistance. And no use
of connecting it in series because the potential difference between two points
on the same line is zero

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How is voltmeter different from potentiometer

Posted by Nidhi Yadav 6 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Sia ? 6 years, 4 months ago

Voltmeter	Potentiometer
Its resistance is high and finite.	Its resistance is high and infinite.
It draws some current from emf source.	It does not draw any electric current from source of emf.
It has low sensitivity	It has high sensitivity
It is a versatile instrument	It measures only emf or potential difference
It is based on the deflection method	It is based on the zero deflection method