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Working principle of moving coil galvanometer?

Posted by Amartya Sarkar 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Kanak Tiwari 7 years, 10 months ago

When a current carrying conductor placed in a external magnetic field line it experience a torque

3Thank You

ANSWER

explain the dielectric polorisation

Posted by Aleena Sijoy 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Shaurya Singh 7 years, 10 months ago

Dielectric polarisation is the phenomena of introducing equal and opposite charges on opposite faces of dielectric by providing ecternal electric field.

1Thank You

Komal Diksha 7 years, 10 months ago

Alignment of polar or non-polar molecules in the presence of external field is said to b dielectric polarisation.

1Thank You

ANSWER

What do you mean by electrical field lines???

Posted by P Bhardwaj 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Muskan Shambhi 7 years, 10 months ago

Electric field lines are the imaginary curves to which the tangents drawn at any point give the direction of the electric field at that point.

2Thank You

ANSWER

Derive an expression for power factor ?????

Posted by Shivi Rajput 7 years, 10 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Is xam idea ,ncert sufficient for CBSE board exam???????PCM

Posted by .Ismat .Jamil 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Priya Prakash S 7 years, 10 months ago

Only ncert text are more than enough

1Thank You

Ishu Chouhan 7 years, 10 months ago

Yes

2Thank You

ANSWER

Derive an expression for drift velocity of electrons in a conductor hence deduced Ohm's law

Posted by Rohan Bhati 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Ishu Chouhan 7 years, 10 months ago

Vd= eE tau/ m

0Thank You

ANSWER

What is the power dissipated in AC circuit containing only L?

Posted by Kalindi Yadav 7 years, 10 months ago

CBSE > Class 12 > Physics

4 answers

Kalindi Yadav 7 years, 10 months ago

Thanks Kanak

2Thank You

Kalindi Yadav 7 years, 10 months ago

For circuit containing inductor L only.Power factor, cosθ=cos 90°=0.

1Thank You

Kanak Tiwari 7 years, 10 months ago

Sorry , Answer is zero because average power is equals to virtual power cos theta here theta is 90 , therefore cos 90 will be zero hence the power dissipated was zero

1Thank You

Kanak Tiwari 7 years, 10 months ago

I think it'zero since cos theta where cos theta

1Thank You

ANSWER

What is the difference between avalanche and zener breakdown?

Posted by Nikhil Khandal 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 7 years, 10 months ago

One of the major difference between the Avalanche and the Zener breakdown is that the Avalanche breakdown occurs because of the collision of the electrons, whereas the Zener breakdown occurs because of the high electric field.Because of this saturation current, the avalanche breakdown mechanism occurs in the diode.

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ANSWER

Why should electrostatic field be zero inside a conductor?

Posted by Kalindi Yadav 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Radhika Tyagi 7 years, 10 months ago

Garima u r 2 gud at physics ?

1Thank You

Kalindi Yadav 7 years, 10 months ago

Because charge on a conductor resides only on the outer surface. Therefore by Gauss theorem, if we draw an imaginary surface just inside the surface of conductor, the surface would enclose no net charge and Flux = integral(E.dS) = netcharge / permittivity integral(E.dS) = 0 E.dS = 0 which gives E = 0

4Thank You

ANSWER

Why objective lens have more appartur than eye lens in microscope

Posted by A A 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 7 years, 10 months ago

The microscope is used in sighting small objects situated nearby. If aperture is large then light ray coming from object expands. So intensity becomes small. If aperture is small then light coming from object expends in small aperture, as a result object is seen more bright. So, aperture is kept small.

1Thank You

ANSWER

Why Cu strips is used in metre bridge?

Posted by Md Hasan 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Ritu Gupta 7 years, 10 months ago

Because copper has very low resistivity due to which it gives exact balance point in the metre bridge

3Thank You

ANSWER

Two like charges kept at vertices of an equilateral triangle.what is the charg at third vertex to get zero potenatial energy

Posted by Shamna Sherin 7 years, 10 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

frequency -5 into 10 to power 19 belongs to which waves?

Posted by Ritu Gupta 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 7 years, 10 months ago

Gamma rays

3Thank You

ANSWER

What is closet approach distance ??????????

Posted by Pankaj Sihag 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Jin Kazama 7 years, 10 months ago

Specially line of e- path and line passes through centre of nucleus

5Thank You

Bunny Jaura 7 years, 10 months ago

The distance between the centres of two objects when they are externally tangent

1Thank You

ANSWER

Define conductance and conductivity. Give si unit

Posted by Akansha Rani 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Bunny Jaura 7 years, 10 months ago

SI unit of conductivity is 'mho' inverse of 'ohm'

4Thank You

Jin Kazama 7 years, 10 months ago

reciprocal of resistance is known as conductance and reciprocal of resistivity is known as conductivity

3Thank You

ANSWER

Explain lenz's law

Posted by Saheba Khatun 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Tannu Pal 7 years, 10 months ago

It state that the direction of an induced current is always such as to oppose the change in the circuit or the magnetic field that produced in it

1Thank You

Komal Diksha 7 years, 10 months ago

Polarity of induced emf is sucg that it tends to oppose the cause which produces it..

1Thank You

ANSWER

What portions are asking in cbse chapers

Posted by Aswathy Mohan 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 7 years, 10 months ago

0Thank You

ANSWER

Why a spring contracts when current is passed through it

Posted by Shreya Pathak 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Tannu Pal 7 years, 10 months ago

Bcoz through a spring it acts magnetic interaction in the coil or spring

2Thank You

ANSWER

The input of common emitter amplifier square to close current gain is 20 if the load resistance is 5 ohm calculate voltage gain transmitter conductance

Posted by Aditi Paliwal 7 years, 10 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is the best publishers sample papers...i want to buy

Posted by Sharma Saabh 7 years, 10 months ago

CBSE > Class 12 > Physics

4 answers

Rochie Joshi 7 years, 10 months ago

Arihant or satish.

0Thank You

Sharma Saabh 7 years, 10 months ago

Vaise whats ur name...

1Thank You

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 7 years, 10 months ago

Agar ye kar liya pura to 100% confirm

1Thank You

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 7 years, 10 months ago

I E Irodov

1Thank You

ANSWER

What is ACL?

Posted by Abdul Wahid 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Abdul Wahid 7 years, 9 months ago

?????

0Thank You

Radhika Tyagi 7 years, 10 months ago

Ampere circuital law

1Thank You

ANSWER

What type of ques. Asked by CBSE related to electromagnetic spectrum

Posted by Akshay Sen 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Chahat Kundra 7 years, 10 months ago

Mostly the role of different rays of spectra are asked and sometimes the roles are given and asked which ray perform following functions.

2Thank You

ANSWER

Reflection of light

Posted by Papa Gff 7 years, 10 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Which field is more strong Magnetic field or Electric field?

Posted by Pravin Chandravanshi 7 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Bunny Jaura 7 years, 10 months ago

0Thank You

Shreya Pathak 7 years, 10 months ago

Electric field

0Thank You

ANSWER

Why in potentiometer the emf by which galvanometer is connect must less than driver cell emf

Posted by Yogesh Kumar 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Preeti Kranti 7 years, 10 months ago

If it is not so the balance point will not be find in the potentiometer wire

3Thank You

ANSWER

What is Eddy current ? --chapter- EM induction.

Posted by Nayan Kumar 7 years, 10 months ago

CBSE > Class 12 > Physics

3 answers

Radhika Tyagi 7 years, 10 months ago

It is a swirling current produced in the bulk of a conductor when magnetic flux linked with a conductor changes.

0Thank You

Garima Suyal 7 years, 10 months ago

It is a type of circular current

0Thank You

Ishu Chouhan 7 years, 10 months ago

An induced current produced in a conductor whenever there is change in magnetic flux linked with conductor called Eddy current . Eddy current is also called unwanted or focault current.

3Thank You

ANSWER

Whats the formula for mutual inductance of two concentric coils

Posted by Anay Patidar 7 years, 10 months ago

CBSE > Class 12 > Physics

1 answers

Nayan Kumar 7 years, 10 months ago

M = (u. N1. N2 . A)/L N1---total no. Of turns in coil 1 N2--total no. Of turns in coil 2 L--lenth of longer coil (when two coils happen to be of different lengths ) A--area of cross section of inner coil

1Thank You

ANSWER

describe the motion of a charge particles in a magnetic field when it enter the field perpendicular to the field lines

Posted by Sumana Das 7 years, 10 months ago

CBSE > Class 12 > Physics