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What is alpha decay

Posted by Anuj Kumar 7 years ago

1 answers

Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two.

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How many questions asked in 2018 from electric charge and fields

Posted by Randhir Kumar 7 years ago

CBSE > Class 12 > Physics

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Whatispathfloarngforc

Posted by Suyash Tripathi 5 years, 8 months ago

CBSE > Class 12 > Physics

0 answers

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In how many questions choice will be there acc. to the latest pattern in physics

Posted by Rajat Dhull 7 years ago

CBSE > Class 12 > Physics

1 answers

O Singh 7 years ago

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Marks of communication system

Posted by Rahul Pratap 7 years ago

CBSE > Class 12 > Physics

2 answers

O Singh 7 years ago

5 marks

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Omparkash Yadav 7 years ago

Only 3 marks

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What is the difference between an n - type and a p- type extrinsic semiconductor ?

Posted by Arti Vishwakarma 7 years ago

CBSE > Class 12 > Physics

2 answers

Yogita Ingle 7 years ago

P type	N Type
A type of extrinsic semiconductor that carries a positive charge and has an improved conductivity.	A type of extrinsic semiconductor that carries a negative charge and has an improved conductivity.
Less electron concentration	Larger electron concentration
Holes are the majority carriers and electrons are the minority carriers .	Electrons are the majority carriers and holes are the minority carriers .
Created by doping an intrinsic semiconductor with acceptor impurities	Created by doping an intrinsic semiconductor with donor impurities

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Sourabh Patel 7 years ago

N type semiconductor are group14 doped with group 15 but in p type semiconductor group 14 is doped with 13

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Define the terms of magnatic permeablity and magnatic susceptibility.

Posted by Pradeep Kumar 7 years ago

CBSE > Class 12 > Physics

1 answers

Anjali Attri 7 years ago

It js defined as the ratio of capacitance of capacitior with dielectrics to capacitance with vacuum.

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At what temperature does the semiconductor behaves as an insulator

Posted by Piyush Chhabra 7 years ago

CBSE > Class 12 > Physics

2 answers

Bedisha Chettri 7 years ago

at 0 degree temperature

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Mohit Bisht 7 years ago

At zero kelvin

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A stone dropped from the top of the tower of height 300m high splashes into the water of a pond near the base of the tower.when is the splash heard at the top ,given that the speed of the sound in air is 340m/s ( g=9.8)

Posted by Chanda Saha 7 years ago

CBSE > Class 12 > Physics

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Guys kya koe whatsapp group vi h study k liye

Posted by Sanjay Singh 7 years ago

CBSE > Class 12 > Physics

2 answers

Srivinayak V 7 years ago

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Aryan Rai 7 years ago

Bhai..hangout pe group bnya hu.. uske liye koi apna gmail id de ni rha.. tumko kya lagta hai.. WhatsApp pe group ke liye.. koi apna number dega!! ? And waise bhi dena bhi ni chahiye.. Number is very much personal

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Why do electric field line doesnot form closed loop?

Posted by Prashansa Preetam 7 years ago

CBSE > Class 12 > Physics

3 answers

Bedisha Chettri 7 years ago

becoz it never intersect eachother.If they intersect than they give two direction of electric field which can not possible. so it never form loop

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Anjali Attri 7 years ago

Because electic fields are not present into the hollow conductir or loop

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Nitika Neb 5 years, 8 months ago

As electric field inside a hollow body is zero so they does not form closed loop

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how potential barrier formed

Posted by Riya Arora 7 years ago

CBSE > Class 12 > Physics

1 answers

Sanjay Singh 7 years ago

When the moving of electrons from n side to p side and holes from p side to n side reaches at equilibrium then a potential which opposes their movement is known as barrier potential

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Why are photodiodes used preferably in the reverse bias condition? A photodiode is fabricated from the semiconductor with the energy band gap of 2.8eV. can it detect a wavelength of 600nm? justify.

Posted by Noor Azam 7 years ago

CBSE > Class 12 > Physics

1 answers

Anjali Attri 7 years ago

Reverse biased photodiode is used to get maxum output signal.

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Explain transistor as a oscillator

Posted by Dolly Sneha 7 years ago

CBSE > Class 12 > Physics

0 answers

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Define one coulomn .

Posted by Saurabh Shivam 7 years ago

CBSE > Class 12 > Physics

2 answers

Bedisha Chettri 7 years ago

one coulomn......charge is 1.6 ×10^19

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Yuvraj Sharma 7 years ago

The force of attraction /repulsion b/w two point stationary charges is equal to the product of charges and sq. Of distace b/w them. F=kq1q2/r^2

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What is segre chart

Posted by Anshu Ski 7 years ago

CBSE > Class 12 > Physics

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Why is photodiode preferably used in reverse bias ?

Posted by Sakshi Ch 7 years ago

CBSE > Class 12 > Physics

1 answers

Shubham Sharma 7 years ago

It is easier to observe change in current wirh change in light intensity

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What is the relation between electric field and electric potential?

Posted by Ritik Thakur 7 years ago

CBSE > Class 12 > Physics

2 answers

Lokendra Patel 7 years ago

E=-dv/dr

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Shubham Sharma 7 years ago

E=v/r

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Polarisation by scattering

Posted by Akash Singh 7 years ago

CBSE > Class 12 > Physics

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Give elementary idea of raman effect ?

Posted by Md Saif 7 years ago

CBSE > Class 12 > Physics

0 answers

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What can be the use of helical motion of a charged particle?

Posted by Md Saif 7 years ago

CBSE > Class 12 > Physics

0 answers

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What is effect of doping on depletion region

Posted by Anurag Ojha 7 years ago

CBSE > Class 12 > Physics

0 answers

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How many diode in half wave rectifier

Posted by Vasi Karan 7 years ago

CBSE > Class 12 > Physics

2 answers

Anjali Attri 7 years ago

Only 1 diode is used

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Jyoti Yadav 7 years ago

One diode

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Define electric potential at a point & derive an expression for the electrostatic potential at a point (1) due to point charge (2) due to electric dipole.

Posted by Rohit Chahar 7 years ago

CBSE > Class 12 > Physics

1 answers

Lokendra Patel 7 years ago

It is the amount of work done in moving a unit positive charge from infinity to that point against the electrostatic forces. And the expression is V=work done /charge

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Show that angle of deviation produced by a thin prism is reduced to one fourth when it is immersed in water

Posted by Yash Taggar 7 years ago

CBSE > Class 12 > Physics

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Does the variation in the actual sunrise and sunset affects the day duration?

Posted by Amisha Nayak 7 years ago

CBSE > Class 12 > Physics

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Ddefine equi potential surface

Posted by Raj Xetri 7 years ago

CBSE > Class 12 > Physics

2 answers

Hardeep Verma 7 years ago

The equipotential surface are those surfaces where the potential is same everyhwere on surface. And the potential difference between any points on surface is zero.

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Shubham Sharma 7 years ago

Where v=0

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Depict the equi potentials surface due an electric dipol

Posted by Raj Xetri 7 years ago

CBSE > Class 12 > Physics