Home
Class 12
PHYSICS
Assertion(A): An applied field will pola...

Assertion(A): An applied field will polarize the polar dielectirc material
Assertion(R ): In polar dielectric each molecular has a permanent diple moments but these are randomly oriented in the absence of an externally applied electric field.

A

Both `A` and `R` are true and `R` is the correct explanation of `A`

B

Both `A` and `R` are True but `R` is not the correct explanation of `A`.

C

`A` is true and `R` is false

D

`A` is false and `R` is true.

Text Solution

Verified by Experts

The correct Answer is:
A
`vec(E)` in outside vicinity of consuctor's surface depends on all the charge present in the space. But the expression
`E=(sigma)/(epsilon_(0))`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTROSTATICS AND GAUSS LAW

    NARAYNA|Exercise Intergers type question|11 Videos

  • ELECTROSTATICS AND GAUSS LAW

    NARAYNA|Exercise Passage VII|3 Videos

  • ELECTROSTATIC POTENTIAL AND CAPACITANCE

    NARAYNA|Exercise ADDITIONAL PROBLEMS|14 Videos

  • EXPERIMENTAL PHYSICS

    NARAYNA|Exercise Comprehension type|6 Videos

Similar Questions

Explore conceptually related problems

How a non polar dielectric develops a net dipole moment when placed in electric field?

How does a non-polar dielectric develop a net dipole moment when placed in electric field?

Knowledge Check

  • In polar dielectrics , tiny electric dipoles are randomly oriented

    A
    in absence of electric field
    B
    in presence of electric field.
    C
    in presence of magnetic field.
    D
    all of these

  • Assertion: In the absence of an external electric field, the dipole moment per unit volume of a polar dielectric is zero. Reason : The dipoles of a polar dielectric are randomly oriented.

    A
    Assertion is correct, reason is correct, reason is a correct explanation for assertion.
    B
    Assertion is correct, reason is correct, reason is not a correct explanation for assertion
    C
    Assertion is correct, reason is incorrect
    D
    Assertion is incorrect, reason is correct

  • Assertion (A): There is no current in the metals in the absence of an electric field. Reason (R) : Motion of free electrons are randomly directed in the absence of an electric field.

    A
    If both assertion and reason are true and the reason is the correct explanation of the assertion.
    B
    If both assertion and reason are true but reason is not the correct explanation of the assertion.
    C
    If assertion is true but reason is false.
    D
    If the assertion is false but reason is true.

    • Similar Questions

    Explore conceptually related problems

    When a dielectric is placed in an electric field, it gets polarized. The electric field in a polarized material is less than the applied field. When a paramagnetic substance is kept in a magnetic field, the field in the substance is more than the applied field. Explain the reason of this opposite behaviour.

    On the basis of your understanding of the following paragraph and the related studied concepts. An electric dipole is a pair of equal and opposite point charges q and -9 separated by a distance '2a'. The total charge of the electric dipole is obviously zero but the field of the electric dipole at a point is non-zero because electric fields due to + qand - q charges at the point do not exactly cancel out. Electric field of a dipole, at large distances, depends on the product 'qa'. So we define a term dipole moment vector vecp of an electric dipole as vecp = q(2a) and its direction is along the line from q to + q charge. The dipole field at large distances fall off as 1/r^3 . Further, the magnitude and direction of the dipole field depends not only on the distance r but also on the angle between the position vector vecr and the dipole moment vecp . Concept of electric dipoles is very significant for different materials. In most molecules, the centres of positive charges and of negative charges exactly coincide and their dipole moment is zero. However they develop a dipole moment when an electric field as applied. Such molecules are termed non-polar molecules. But in some molecules, the centres of positive charges do not exactly coincide with that of negative charges and the molecules has a permanent dipole moment even in the absence of an electric field. Such molecules are called polar molecules. Various materials give rise to interesting properties and important applications in the presence or absence of electric field. Distinguish between polar and non-polar molecules. Give examples too.

    Assertion: In the absence of an external electric field, the dipole moment per unit volume of a polar dicletric is zero. Reason : The dipoles of a polar diclectric are randomaly oriented.

    Assertion: Polar mlecules have permanent dipole moment. Reason : In polar molecule, the centres of positive and negative charges coincide evcen wehen there is no external field.

    Assertion: When a dielectric material is kept inside some external electric field then the net electric field intensity inside the volume of dielectric is always less than external electric field intensity. Reason: In a normal state, polar molecules of dielectric material are randomly oriented and their net electric field remains zero. If we apply electric field on a dielectric material then the polar molecules experience torque and gets aligned along its direction.

    Home
    Profile