Electric Field inside a Conductor under Electrodynamic Conditions

Q.

What-is-p type-and-n type semiconductor?

Q. 41. Two charges of +25 × 10–9 coulomb and –25 × 10–9 coulomb are placed 6 m apart. Find the electric field intensity ratio at points 4 m from the centre of the electric dipole (i) on axial line (ii) on equatorial line (1) 1000 49 (2) 49 1000 (3) 500 49 (4) 49 500

Q.

Why electric current is a scalar with definition

Q.

The electric field inside a spherical shell of uniform surface charge density is____.

Q. Find the number of free electrons per unit volume of a metallic wire of density ${10}^4{\text{kg/m}}^3$ and atomic mass number $100$. The number of free electrons per atom is one.

1. $6.022\times {10}^{23}$
2. $6.022\times {10}^{25}$
3. $6.022\times {10}^{28}$
4. $6.022\times {10}^{30}$

Q. The intensity of an electric field depends only on the coordinates $x$ and $y$ as follows:
$E=\frac{a(x\hat{i}+y\hat{j})}{x^2+y^2}$
where, $a$ is a constant and $\hat{i}$ and $\hat{j}$ are the unit vectors of the $x$ and $y-$ axes. Find the charge within a sphere of radius $R$ with the centre at the origin.

1. $2\pi {ϵ}_{0}aR$
2. $4\pi {ϵ}_{0}aR$
3. $\pi {ϵ}_{0}aR$
4. $-2\pi {ϵ}_{0}aR$

Q. a parallel plate capacitor C is charged with a battery of emf V volt. a dielectric slab of dielectric cons†an t K is placed between the plates to fully ocupy the space. the battery remains connected . the new electrostatic force of attraction between the plates F is related woth initial force F as ?

Q. find the electric potential at the point O due to segment of ring that make angle 60 degree at centre whose linear charge density is 4 C/m is ?

Q. 57.A conductor PQ, carrying a current i is placed perpendicular to a long conductor xy carrying a current i. the direction of force on PQ will be

Q. 39.The electric potential on the surface of a sphere of radius R and charge 3X10^-6 C is 500 V. The intensity of electric field on the surface of the sphere is?

Q.

When a pure semiconductor is heated, its resistance_________

Q.

Under electrostatic conditions electric field inside a conductor is zero but in electrodynamic condition the field is not equal to zero, how field develop inside a conductor in electrodynamic condition.

Q. $A$ straight cylindrical wire of infinite length produces electric field of $9\times {10}^4{\text{NC}}^{-1}$ at a distance of $10\text{cm}$. Linear charge density of wire is

​​​​​​​$[$1 Mark$]$

1. $0.1\frac{\mu \text{C}}{\text{m}}$
2. $0.5\frac{\mu \text{C}}{\text{m}}$
3. $50\frac{\mu \text{C}}{\text{m}}$
4. $10\frac{\mu \text{C}}{\text{m}}$

Q. 32.Calculate electric field intensity at point 5m from a charge of 100uc in the vacuum

Q. Unit of dielectric strength is

1. Volt /meter
2. Newton /coulomb
3. (Tesla) (m) /sec
4. All of the above

Q. A charge $Q$ is uniformly distributed over the surface of a right circular cone of semi-vertical angle $\theta$ and height $h$. The cone is uniformly rotated about its axis at angular velocity $\omega$. The associated magnetic dipole moment will be:

1. $\frac{Q\omega }{2}\frac{h^2{\tan }^2\theta }{\sec \theta }$
2. $\frac{Q\omega }{4}\frac{h^2{\tan }^2\theta }{\sec \theta }$
3. $\frac{Q\omega }{2}{h}^2{\cos }^2\theta$
4. $\frac{Q\omega }{4}{h}^2{\sin }^2\theta$

Q.

How Can I Make A Diode?

Q. Given below are two statements, Assertion$\left(A\right)$ and Reason$\left(R\right)$.

Assertion$\left(A\right)$: A negatively charged particle is projected near a current carrying conductor along the direction of current, then the negative charge moves away from the conductor.

Reason$\left(R\right)$: The current carrying conductor produces magnetic field and the moving charge also produces magnetic field.

1. Both Assertion and Reason are true, and Reason is the correct explanation for Assertion.
2. Both Assertion and Reason are true, and Reason is not the correct explanation for Assertion.
3. Assertion is true, but Reason is false.
4. Assertion is false, but Reason is true.

Q. Satrajit had learned in electrostatics that the electric field inside a conductor is always zero. Now they are telling him that when current flows, an electric field gets set up inside a conductor which drifts the electrons, thus making the current flow. This makes no sense to him.
It makes no sense to him because

1. He doesn’t understand that electric field inside a conductor is zero only under electrostatic conditions
2. He thinks electric field is not a vector.
3. They are telling him some random things which has no science in it
4. He thinks electric field is non conservative.

Q.

Two parallel wires 1 m apart carry currents of 1 A and 3 A respectively in opposite directions. The force per unit length acting between two wires is

1. $6\times {10}^{-5}N{m}^{-1}$ repulsive

2. $6\times {10}^{-7}N{m}^{-1}$ repulsive

3. $6\times {10}^{-5}N{m}^{-1}$ attractive

4. $6\times {10}^{-7}N{m}^{-1}$ attractive

Q.

What is the quantum of electric charge?

Q.

(a) Consider an arbitrary electrostatic field configuration. A small test charge is placed at a null point (i.e., where E = 0) of the configuration. Show that the equilibrium of the test charge is necessarily unstable.

(b) Verify this result for the simple configuration of two charges of the same magnitude and sign placed a certain distance apart.

Q. A spherical conductor of radius $50\text{cm}$ has charge of $3.6\mu \text{C}$ distributed over its surface. What is magnitude of electric field at a point $150\text{cm}$ from the centre of the conductor?

1. $1.44\times {10}^4\text{V/m}$
2. $3.6\times {10}^3\text{V/m}$
3. $1.22\times {10}^5\text{V/m}$
4. $6.2\times {10}^4\text{V/m}$

Q.

What force causes oppositely charged particles to attract each other?

Q.

Why does alternating current not show magnetic effects?

Q. Two charges are placed at vertices of an equilateral triangle, what is the direction of electric field at the third vertex?

1. A
2. B
3. C
4. D

Q. Electric charge Q is uniformly distributed on a thin semi circular ring of radius R. The potential at the centre of the ring will be

Q. A circuit containing a $80mH$ inductor and a$60\mu F$ capacitor in series is connected to a $230V,50Hz$ supply. The resistance of the circuit is $15\Omega .$ Obtain the average power transferred to each element of the circuit, and the total power absorbed

Q. The density of a nucleus in which mass of each nucleon is 1.6710 to the power of minus 27kg and R^°=1.410 to the power of minus 15m is

Q.

If finding the electric field around a surface is given by $\left|\overrightarrow{E}\right|=\frac{q_{enc}}{{\epsilon }_0\left|A\right|}$ is applicable. In the formula ${\epsilon }_0$ is permittivity of free space, $A$ is area of Gaussian and $q_{enc}$ is charge enclosed by the Gaussian surface. This equation can be used in which of the following situation?

1. For any Gaussian surface.

2. Only when Gaussian surface is an equipotential surface.

3. Only when electric field is constant on the surface.

4. Equipotential surface and electric field is constant on the surface.