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If we rub glass rod with silk cloth .What charges will the glass rod and the silk cloth get? Which get + ve and which get - ve??

Posted by Aadi Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Vikas Shukla 5 years, 3 months ago

No, it is not due to induction. Yrr silk cloth is rubbed over glass rod i. e. They are in contact so there won't be any induction and there won't be any conduction too because they were neutral initially. So here is charging due to friction ( electrons are transferred from lower work function body to higher work function body.)

1Thank You

Anish Kumar 5 years, 3 months ago

The rods gets +ve charge and silk get -ve by concept ofchrge by induction

2Thank You

Khushi....? ??‍? 5 years, 3 months ago

By loosing electron glass rod will be +vely charged and silk cloth will be -vely charged.....

3Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Glass rod = positive charge. Silk = Negative charge due to loose electron and gain electron from both.

2Thank You

Vikas Shukla 5 years, 3 months ago

Glass rod will loose some electrons which will be acquired by silk. Therefore glass rod will acquire +ve charge and silk cloth will acquire -ve charge.

2Thank You

ANSWER

Numerical on Kirchoff second law

Posted by Sonika Sonika 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Condition for total internal refraction

Posted by Anshika Sahiba 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 5 years, 3 months ago

The two conditions for total internal reflection :

1. The ray of light must travel from a denser medium into a rarer medium.

2. The angle of incidence in the denser medium must be greater than the critical angle for that pair of media.

3Thank You

ANSWER

Why meganitc feild

Posted by Subrajit Shill 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Anish Kumar 5 years, 3 months ago

Because particle contains +ve and-ve charge due they have shows attraction or repulsion

0Thank You

Khushi....? ??‍? 5 years, 3 months ago

What do you want to say....????

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ANSWER

Toroid forces between two infinitely long straight parallel conduction carrying current definition of amphere

Posted by Mausam Chahal 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

The force between the two parallel conductors is attractive in nature if the current is flowing in same direction in both the conductors whereas the force is repulsive if the current is flowing in opposite direction in the conductors.

One ampere of current through each of two parallel conductors of infinite length, separated by one meter in empty space free of other magnetic fields, causes a force of exactly 2 × 10−7 N/m on each conductor.

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ANSWER

Magnetic field due to current carrying wire of infinite length

Posted by Mausam Chahal 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Khushi....? ??‍? 5 years, 3 months ago

dB=(k dl sin thita)/r^2...

1Thank You

ANSWER

Differences between power dessipation and average power in LCR circuit...

Posted by Khushi....? ??‍? 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Khushi....? ??‍? 5 years, 3 months ago

Thanks but can you answer my questions....

1Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Mere ko lagta hai tum padhne me bahut acchi ho iss app par tum hi jayada question ka ans detee ho. Keep going. All the best from my side for class 12 board and IIT JEE/ADV.

1Thank You

ANSWER

Quality factor of resonance circuit or sharpness of resonance circuit.....

Posted by Khushi....? ??‍? 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

The quality factor relates the maximum or peak energy stored in the circuit (the reactance) to the energy dissipated (the resistance) during each cycle of oscillation meaning that it is a ratio of resonant frequency to bandwidth and the higher the circuit Q, the smaller the bandwidth, Q = ƒr /BW. Q factor of series resonant circuit is defind as the ratio of the voltage developed across the inductance or capacitance at resonance to the impressed voltage, which is the voltage applied across R. Q is inversely proportional to R. So, if R increases Q factor of circuit decreases or if R decreases Q increases.

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ANSWER

What is mobility.Significance of mobility in drift velocity.

Posted by Khushi....? ??‍? 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Kareena Yadav 5 years, 3 months ago

It is the ratio of drift velocity to electric field.

1Thank You

Akhil Khare 5 years, 3 months ago

Drift Velocity per unit Electric field is known as Mobility.

2Thank You

Aakash Kumar 5 years, 3 months ago

mobility is defined as ratio of modulus of drift velocity to electric field applied. It is always positive. It is same for a particular metal wire with same dimensions under any potential difference.

2Thank You

ANSWER

Drift velocity,relation between drift velocity and electric current

Posted by Mausam Chahal 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Khushi....? ??‍? 5 years, 3 months ago

The average velocity of free electrons with which the electrons start moving from lower potential to the higher potential under the action for external electric field is called drift velocity Electric current is directly propertional to the drift velocity. I=neAVd where Vd is drift velocity.... and I is current..

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ANSWER

Why we use gauss's law? If we have formula to find electric field on point charge . Formula of electric field in long infinite linear charge distribution. (Give two formula.)

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Khushi....? ??‍? 5 years, 3 months ago

So sorry I didn't mind it....the formula....is..E=lambda/(2 pi epsilon not × r) and E=q/(2 pi epsilon not × r × l)...

2Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

I m asking the formula of infinite linear charge.

1Thank You

Khushi....? ??‍? 5 years, 3 months ago

Two formula are phi=q/epsilon not and phi=closed integral of Eds

3Thank You

Khushi....? ??‍? 5 years, 3 months ago

Gauss law is used for closed surface that should be mentioned properly...

4Thank You

Khushi....? ??‍? 5 years, 3 months ago

Gauss's Law is a general law applying to any closed surface. It is an important tool since it permits the assessment of the amount of enclosed charge by mapping the field on a surface outside the charge distribution. For geometries of sufficient symmetry, it simplifies the calculation of the electric field.

4Thank You

ANSWER

The electric field at a point on the equatorial line of a small electric dipole is 10 N/C What will be the electric field at a point situated at the same distance on the axis of the dipole ?

Posted by Sai Baishnabi 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Khushi....? ??‍? 5 years, 3 months ago

Yes this is right 20N/c

3Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Electric field at a point situated at the same distance on the axis of dipole is 20N/c. Because 2 times of of electric field of axial dipole is equal to the electric field of equatorial point of dipole.so here KP/x^3 =10 so 2kp/x^2=20N/c

2Thank You

ANSWER

The force come out in newton when charge is in coulomb ,, if charge is in micro coulomb then force unit will be????? Explian plzz...

Posted by Shilpi Mishra 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Rohit Krishna 5 years, 3 months ago

She asked to explain and that's why I did like that.My apologies.

3Thank You

Rohit Krishna 5 years, 3 months ago

Ok then sorry for my mistake...Thank you for pointing it out..

3Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Rohit i want to say that don't elaborate to much for small things this affect others to understand by your language. Hope you understand me.?

3Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Change the micro coulomb into coulomb.from this you have both value is standard.force in (N)and charge in (c). 1 micro coulomb = 10^-6 coulomb.

3Thank You

Rohit Krishna 5 years, 3 months ago

I think there won't be any change in the unit because from the equation Force F= qE, we know that unit of charge q as given above is microcoulomb,and SI unit of electric field is N/C .Therefore if charge is given in microcoulomb,then you can understand that unit of electric field will also change accordingly to N/ microcoulomb.Therefore both will cancel each other as per the equation qE and thus you will obtain the answer as N itself.(Alter: You don't need to follow such huge steps to arrive at the answer.Just convert microcoulomb to coulomb before substituting as usually any problem is solved in that way).

2Thank You

ANSWER

Magnetic moment due to a bar magnet is same as the magnetic moment due to a solenoid or not??If yes then explain....

Posted by Khushi....? ??‍? 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Khushi....? ??‍? 5 years, 3 months ago

Okk

1Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Still i m not read this chapter sorry? but very soon i read this .

1Thank You

ANSWER

Pole strength of a bar magnet depends on its area,but the unit of area is not included in the unit of pole strength(Am).Why?

Posted by Rohit Krishna 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Khushi....? ??‍? 5 years, 3 months ago

Since the formula of magnetic moment is M=IA and its unit is Am^2 and the formula of pole strength is m=M/2L hence its correct formula is m=IA/2L the unit of L is m and unit of A is m^2 hence Area is present in the unit but it is cancelled due to division by the length...Pole strength is given by m=M/2l. Unit of magnetic dipole moment is Am^2 Therefore, unit of pole strength will be Am

3Thank You

ANSWER

An infinite line charge produces a field of 9 into 10 to the power 4 Newton per coulomb at a distance of 2 cm calculate the linear charge density

Posted by Kuhu Singh 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Aakash Kumar 5 years, 3 months ago

Electric field at d distance from a uniformly charged rod =k×2 ×linear charge density /d

1Thank You

Aakash Kumar 5 years, 3 months ago

E=k×2× linear charge density /distance Linear charge density =E×d/2k=9×10⁴×2×10^-²/2×9×10^9=10^-7 C/m or 0.1 microC/m

1Thank You

Khushi....? ??‍? 5 years, 3 months ago

Apply the formula lambda=2 pi epsilon not E×d the answer will be 1.0008×10^-7..

2Thank You

ANSWER

A particle of mass M and charge Q is released from rest in a uniform electric field of intensity calculate the kinetic energy it attains after moving a distances between the plates

Posted by Kuhu Singh 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Aakash Kumar 5 years, 3 months ago

KE attained =Work done =Force ×Distance =(Electric field ×charge) ×distance =qEd=answer

0Thank You

ANSWER

An electric dipole of dipole moment 4 x 10-5 C m is placed in a uniform electric field of 10-3 N C-1 making an angle of 30° with the direction of the field. Determine the torque exerted by the electric field on the dipole ?

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Krishna 5 years, 3 months ago

Torque=PEsin theta where Pis the dipole moment, E is the electric field at that point and theta is the angle between dipole moment and electric field.Substituting you will get torque= 4 × 10^-5 × 10^-3 × sin30°= 4× 10^-8 × 1/2 = 2 × 10^-8 Nm.....I hope this is the answer..

0Thank You

ANSWER

What do you mean by gauss's law and gaussian surface??

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

4 answers

Shilpi Mishra 5 years, 3 months ago

Guass law states that.. The net electric flux through a closed ( 3-d) surface is 1/£0 times the net charge enclosed by the surface..

2Thank You

Khushi....? ??‍? 5 years, 3 months ago

According to Gauss's law, the flux of the electric field →E through any closed surface, also called a Gaussian surface, is equal to the net charge enclosed (qenc) divided by the permittivity of free space (ϵ0): ΦClosedSurface=qencϵ0.

2Thank You

Ravi Shankar 5 years, 3 months ago

A Gaussian surface is a closed surface in 3D space through which the flux of a vector field is calculated

1Thank You

Ravi Shankar 5 years, 3 months ago

According to this law, the surface integral of electric field over a closed loop is equal to 1/e times of charge enclosed on it

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ANSWER

A cell of emf E and internal resistance r draws a current. Write the relation between terminal voltage V in terms of E, I and R

Posted by Cts Gaming 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Khushi....? ??‍? 5 years, 3 months ago

v = E - Ir...

1Thank You

ANSWER

If mass of the electron = 9.1 x 10−Kg. Charge on the electron = 1.6 x 10− coulomb and g= 9.8 ?/?. Then the intensity of the electric field required to balance the weight of an electron is 5.6 x 10−?/? 5.6 x 10−?/? 5.6 x 10−?/? 5.6 x 10−7 ?/?

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Krishna 5 years, 3 months ago

If the intensity of the electric field balances the weight of the electron, use the equation qE = mg. where q is the charge, E is the electric field at that area, m is the mass of electron and g is the acceleration due to gravity. Substituting the values given in the question to the corresponding ones in the equation , you will get the answer as 5.6 × 10 ^ –12 N/C ( Note that in an entrance point of view,you can take 10 instead of 9.8 for g and if it is given as 9.8 m/s^2 in the question only,you have to take accordingly.But in this case if you substitute 9.8 in the equation as given in the question, you will be just close to the answer.For the actual answer you have to substitute 10 for the correct answer.)

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ANSWER

Which have greatest critical angle? 1.water-air interphase 2.diamond -air interphase..

Posted by Vishnu Modi 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Khushi....? ??‍? 5 years, 3 months ago

2nd one obviously

2Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

2nd.

2Thank You

? ? 5 years, 3 months ago

Sin of critical angle is inversely proportional to refractive index so the medium having low refractive index will have a higher critical angle so it should be water air interface

1Thank You

ANSWER

Two electirc bulbs p and q have their resistances in the ratio 1:2. they are connected in series across a battery. Find the ratio of power dissipated in these bulbs

Posted by Sankhadeep Dutta 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Khushi....? ??‍? 5 years, 3 months ago

1:2 ;as R1:R2 is given 1:2 and formula of power is p=I^2R and since both bulbs are in series hence I(current) is constant.. hence p1/p2=(I^2R1)/(I^2R2) when you will solve this you will get 1:2 that is the ratio and required answer...

2Thank You

ANSWER

Net Electric flux in closed surface area???

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Kareena Yadav 5 years, 3 months ago

No. Of electric field lines pass through the area

0Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Thnq

1Thank You

Khushi....? ??‍? 5 years, 3 months ago

Where Q is net charge...

2Thank You

Khushi....? ??‍? 5 years, 3 months ago

The total of the electric flux out of a closed surface is equal to the charge enclosed divided by the permittivity. The electric flux through an area is defined as the electric field multiplied by the area of the surface projected in a plane perpendicular to the field. It is represented by Phi=Q/epsilon not which is gauss law....

2Thank You

Yogita Ingle 5 years, 3 months ago

Electric flux is a measure of number of field lines crossing a given surface area.

It is given by the algebraic sum of all the charges inside the closed surface area divided by permittivity.

ϕ=qnet/ϵ_o

0Thank You

ANSWER

How many chapter has been completed guys

Posted by Shahana Perwin 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Electric field due to ring at point p???

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Aakash Kumar 5 years, 3 months ago

Electric field at x distance away from the center given by kQx/(r²+x²) ³/²

1Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Shi hai thnq

2Thank You

Khushi....? ??‍? 5 years, 3 months ago

This expression is same as the electric field intensity due to a point charge at a distance x from the point charge q. Thus, ring behaves like a point charge if the point of observation is far away from the ring as compared to the radius of the ring.

2Thank You

Ayush Vishwakarma?? 5 years, 3 months ago

Is this behaves like a point charge? If yes explain.

1Thank You

Khushi....? ??‍? 5 years, 3 months ago

The electric field of a ring of charge on the axis of the ring can be found by superposing the point charge fields of infinitesmal charge elements. ... This is a suitable element for the calculation of the electric field of a charged disc. E=kQx/(R^2+a^2)^3/2...

3Thank You

ANSWER

What is relative permitivitty

Posted by Asad Faruqui 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 5 years, 3 months ago

Relative permittivity is the factor by which the electric field between the charges is decreased relative to vacuum. Likewise, relative permittivity is the ratio of the capacitance of a capacitor using that material as a dielectric, compared to a similar capacitor that has vacuum as its dielectric.

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ANSWER

Name of main topic im ch 1

Posted by Utkarsh Srivastav 5 years, 3 months ago

CBSE > Class 12 > Physics