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Sample paper is just an idea to know what is the pattern of upcoming question paper and who the marks are divided.. It doesnt means that question given sample paper will come in exam. If they come its ur luck

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si unit of sigma

Posted by Guddu Masih 5 years, 7 months ago

CBSE > Class 12 > Physics

3 answers

Riya Rana 5 years, 7 months ago

C/m^2

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Geetanjali Rathod 5 years, 7 months ago

Compare to second sigma is smaller unit

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Geetanjali Rathod 5 years, 7 months ago

1 sigma =10 *-6 second

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two identical charged particles moving with same speed enter a region of uniform magnetic field if one of these enter normal to the field direction and other enters along a direction at 30 degree with the field what would be the ratio of their angular frequencies?....choose--a)1:2 or b)1:1??

Posted by Muskaan Vig 5 years, 7 months ago

CBSE > Class 12 > Physics

5 answers

Gaurav Kumar 5 years, 7 months ago

1:1

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Tamanna Sharma 5 years, 7 months ago

When perpendicular to the field qvB = mv^2/ r,hence angular frequency is v/ r= qB/m,,,,and at angle 30° qvsin30°B= mvsin30° ^2/r hence angular frequency is vsin30°/r = qB/ m .in both cases a.f is same so ratio is 1:1

4Thank You

A ? 5 years, 7 months ago

1 : 2

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Muskaan Vig 5 years, 7 months ago

please tell me why?

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Riya Rana 5 years, 7 months ago

1:1

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The resultant of two forces 10N and 15N along +xaxis and -xaxis is respectively???

Posted by Javali Jonu 5 years, 7 months ago

CBSE > Class 12 > Physics

1 answers

Tamanna Sharma 5 years, 7 months ago

-5N it's colinear vector ( anti parallel in this case)

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ANSWER

A wire has resistance of 12 ohm it is bent in the form of circle the effective resistance between the two point on the diameter of the circle is

Posted by Ajay Sharma 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Shatayu Ganvir 5 years, 7 months ago

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Ajay Sharma 5 years, 7 months ago

The two semicircular part each of 6 ohm are in parallel 6×6/6+6 = 36/12 = 3 ohm

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Relation between electric field and current density

Posted by Ajay Sharma 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Yogita Ingle 5 years, 7 months ago

Current density J is a vector quantity which is defined as the current flowing per unit area measured in a direction normal to the direction of flow of charge.

|J| = |I|/ A

Substituting the value of I and Vd in this equation |J| = |I|/ A ;

|J|= nAqVd / A

= nq. (qt|E|/ m)

|J| = (nq²t/ m).|E|

The vector J is parallel to the electric field vector.

In the above equation the quantity nq²t/ m is called conductivity σ.

|J| = (nq²t/ m).|E| = σ |E|

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Tamanna Sharma 5 years, 7 months ago

J= sigma E

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I have maximum of the questions but still i am not confident about it

Posted by Koshal Kumar 5 years, 7 months ago

CBSE > Class 12 > Physics

3 answers

Becky Shoshannah 5 years, 7 months ago

U'll do great! Just believe in yourself and God

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Koshal Kumar 5 years, 7 months ago

To kya karu

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Riya Rana 5 years, 7 months ago

Happens with everyone

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Bye friends....again all the very best

Posted by Nikita Beniwal 5 years, 7 months ago

CBSE > Class 12 > Physics

1 answers

A ? 5 years, 7 months ago

Byeee...????✌✌?

2Thank You

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A rectangular wire frame is placed in a uniform magnetic field directed upwards and normal to the plane of paper. The part AB is connected to a spring . the spring is stretched and released when the wire AB has come to the position A'B' (t=0). How would the induced emf vary with time? Neglect damping

Posted by Sonakshi Raj 5 years, 7 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is electric flux ?and its SI unit with dimension

Posted by Rohit Saklani 5 years, 7 months ago

CBSE > Class 12 > Physics

4 answers

Apoorva Rao 5 years, 7 months ago

NCm-2

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Apoorva Rao 5 years, 7 months ago

Electric Flux is the no.of electric field lines passing through a surface area normally

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Prafull Jha 5 years, 7 months ago

No of electric field lines passing perpendicular to the surface is called electric flux. SI unit- (N/C)m^2 Dimension-ML^3T^-3A^-1

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Nikita Beniwal 5 years, 7 months ago

No. Of electric field lines passing through particular area

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All the best for board 2020...

Posted by Nikita Beniwal 5 years, 7 months ago

CBSE > Class 12 > Physics

4 answers

Nikita Beniwal 5 years, 7 months ago

Welcome

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Kriti Sharma 5 years, 7 months ago

Thanks niki......??????

1Thank You

Manvendra Singh 5 years, 7 months ago

Same to you

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A ? 5 years, 7 months ago

Same to u...?

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ANSWER

Principal of half wave rectifier?

Posted by Ankur Dahiya 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Prafull Jha 5 years, 7 months ago

it is based on the fact that diode conduct electricity or allow to pass current through it. it conduct electricity in FB and does not conduct in RB.

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Manvendra Singh 5 years, 7 months ago

Spelling of principle is wrong

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Main topics to learn ?

Posted by Shivam Yadav 5 years, 7 months ago

CBSE > Class 12 > Physics

1 answers

Nilesh Hiragar 5 years, 7 months ago

Bro all the topic r main

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Prove that in a radial magnetic field the deflection of coil is directly proportional to the current flowing in the coil

Posted by Kirthi Prabhudessai 5 years, 7 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Name the EM waves used for studying crystal structure of solids

Posted by Josna Mary Thomas Thomas 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Muskaan Vig 5 years, 7 months ago

X-Rays are used for studying crystal structure of solids..

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Ritwik Choudhary 5 years, 7 months ago

Gamma rays

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Name the elements which shows +3 oxidation state?

Posted by Prakash Kumar 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Shefu ??????? 5 years, 7 months ago

Scandium and group 15 elements

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Riya Rana 5 years, 7 months ago

Scandium

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Sir 2021 ka syllabus kab aayega

Posted by Dilnawaz Farooqui 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Tushar Bhola 5 years, 7 months ago

Bhai fail hokar fir se 12 karni hai kya

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Tamanna Sharma 5 years, 7 months ago

3000 tak aa jayga

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While deriving potential due to dipole how do we find r1 and r2?

Posted by Sunita Devi 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Riya Rana 5 years, 7 months ago

Okk

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Sunita Devi 5 years, 7 months ago

I got it

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ANSWER

What is one side deflection?when it occur and how can we rectify it?

Posted by Prafull Jha 5 years, 7 months ago

CBSE > Class 12 > Physics

1 answers

Tamanna Sharma 5 years, 7 months ago

1. When the source cell emf is less than to the comparable cell.,,,,2.when connection is not right.(+ve of potentiometer is connected to the-ve of the cell which we have to compare. ...rectify it by making right connections and suitable emf cell choosen.

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Principal of cyclotron

Posted by Abdul Raziq 5 years, 7 months ago

CBSE > Class 12 > Physics

4 answers

Arpita Mengi 5 years, 7 months ago

It works on the the principle that when a charged particle moving normal to mag. Field it feels the magnetic force due to which it starts moving in circular path

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Sg Tech 5 years, 7 months ago

Time taken for one revolution is independent of its speed and radius

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Sanskriti Sinha 5 years, 7 months ago

Cyclotron works on the principal of mutually perpendicular electric and magnetic field.

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Prafull Jha 5 years, 7 months ago

A charge particle can acquire very high K.E by crossing the same electric field again and again with the help of uniform perlendicular magnetic field

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Youngs double slit experiment derivation

Posted by Parth Deshmukh 5 years, 7 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Does our syllabus contain limit of resolution??

Posted by Aryan Bhavsar 5 years, 7 months ago

CBSE > Class 12 > Physics

1 answers

Bhanu Arora 5 years, 7 months ago

Yes, its a part of wave optics' resolving power of telescope and microscope

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ANSWER

Important question of chapter wave optics

Posted by Suchi Mishra 5 years, 7 months ago

CBSE > Class 12 > Physics

4 answers

Mitali Jain 5 years, 7 months ago

Polarisation and Young's experiment

2Thank You

A ? 5 years, 7 months ago

Ydse

1Thank You

Pooja Rawat 5 years, 7 months ago

Polarisation topic

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Tevar Jaat 5 years, 7 months ago

Double slit experiment

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What is reason behind reverse breakdown ?

Posted by Naina20 Tiwari 5 years, 7 months ago

CBSE > Class 12 > Physics

3 answers

Naina20 Tiwari 5 years, 7 months ago

Thank you

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Rajat Barwar 5 years, 7 months ago

Drastic breaking of large no. of covalent bonds.

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Manjay Jha 5 years, 7 months ago

Current is quite small and is independent of voltage.

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Derive the electric field intensity at axial line

Posted by Ramsha Faiz 5 years, 7 months ago

CBSE > Class 12 > Physics

2 answers

Apoorva Rao 5 years, 7 months ago

Considering an electric dipole ab =2a and a point p is in the axial position with dipole movement p=q.2a Electric field intensity at point p due to +q=1/4pie€0. q1q2/r²- a² Electric field intensity at point of due to _q=1/4pie€0.q1q2/r²+a² Net electric field intensity =E1+E2=2rp/(r²-a²)²

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Sunita Devi 5 years, 7 months ago

You can watch video from lesson to know that

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What we have to study about De Broglies explanation of Bohrs 2nd postulate

Posted by Josna Mary Thomas Thomas 5 years, 7 months ago

CBSE > Class 12 > Physics