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Working principle of moving coil galvanometer?

Posted by Amartya Sarkar 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kanak Tiwari 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Shaurya Singh 8 years, 1 month 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 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Muskan Shambhi 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

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

Posted by .Ismat .Jamil 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Priya Prakash S 8 years, 1 month ago

Only ncert text are more than enough

1Thank You

Ishu Chouhan 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ishu Chouhan 8 years, 1 month ago

Vd= eE tau/ m

0Thank You

ANSWER

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

Posted by Kalindi Yadav 8 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Kalindi Yadav 8 years, 1 month ago

Thanks Kanak

2Thank You

Kalindi Yadav 8 years, 1 month ago

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

1Thank You

Kanak Tiwari 8 years, 1 month 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 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Radhika Tyagi 8 years, 1 month ago

Garima u r 2 gud at physics ?

1Thank You

Kalindi Yadav 8 years, 1 month 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

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ANSWER

Why objective lens have more appartur than eye lens in microscope

Posted by A A 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ritu Gupta 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

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

Posted by Ritu Gupta 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

Gamma rays

3Thank You

ANSWER

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

Posted by Pankaj Sihag 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Jin Kazama 8 years, 1 month ago

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

5Thank You

Bunny Jaura 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Bunny Jaura 8 years, 1 month ago

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

4Thank You

Jin Kazama 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Tannu Pal 8 years, 1 month 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 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 8 years, 1 month ago

0Thank You

ANSWER

Why a spring contracts when current is passed through it

Posted by Shreya Pathak 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Tannu Pal 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

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

Posted by Sharma Saabh 8 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Rochie Joshi 8 years, 1 month ago

Arihant or satish.

0Thank You

Sharma Saabh 8 years, 1 month ago

Vaise whats ur name...

1Thank You

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 8 years, 1 month ago

Agar ye kar liya pura to 100% confirm

1Thank You

Mmmmmmmmmmmmmmmmmmmm Wwwwwwwwwwwwwwwwwwww 8 years, 1 month ago

I E Irodov

1Thank You

ANSWER

What is ACL?

Posted by Abdul Wahid 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Abdul Wahid 8 years, 1 month ago

?????

0Thank You

Radhika Tyagi 8 years, 1 month ago

Ampere circuital law

1Thank You

ANSWER

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

Posted by Akshay Sen 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Chahat Kundra 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Which field is more strong Magnetic field or Electric field?

Posted by Pravin Chandravanshi 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Bunny Jaura 8 years, 1 month ago

0Thank You

Shreya Pathak 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Preeti Kranti 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Radhika Tyagi 8 years, 1 month 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 8 years, 1 month ago

It is a type of circular current

0Thank You

Ishu Chouhan 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Nayan Kumar 8 years, 1 month 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 8 years, 1 month ago

CBSE > Class 12 > Physics