Electric Field Due to a Line of Charge along Its Axis

Q. 73.Two charges each of magnitude Q are fixed at a distance 2a distance apart. A third charge(-q of mass m) is placed at the mid point of the two charges; now -q charge is slightly displaced perpendicular to the line joining the charges then find its time period.

Q. A particle of charge -q & mass m moves in a circle of radius r around an infinitely long line charge having linear charge density +λ. Then time period will be--

1. 

2. 

3. 

4. 

Q. A charge particle (-q) is placed along the axis of uniformly charged fixed ring of radius R. Initially charge is released from its position (2R, 0, 0), predict its motion. 1) Periodic motion 2) SHM 3) Uniform motion 4) Charge particle does not return to its initial position.

Q. A particle of mass m and charge+q1 moves diametrically through a uniformly charged sphere of radius R with total charge -q2. If +q1 performs SHM, then its time period is?

Q.

According to Gauss Theorem, electric field of an infinitely long straight wire is proportional to

1. r

2. 
   

3. 
   

4. 
   

Q. Two parallel metallic plates have surface charge densities ${\sigma }_1$ and ${\sigma }_2$ as shown in figure. Match the following.

Table-1 Table-2

$\left(\text{A}\right)$ If ${\sigma }_1+{\sigma }_2=0$	$\left(\text{P}\right)$ Electric field in region $\text{III}$ is towards right.
$\left(\text{B}\right)$ If ${\sigma }_1+{\sigma }_2>0$	$\left(\text{Q}\right)$ Electric field in region $\text{I}$ is zero.
$\left(\text{C}\right)$ If ${\sigma }_1+{\sigma }_2<0$	$\left(\text{R}\right)$ Electric field in region $\text{I}$ is towards right.
$\left(\text{S}\right)$ None.
$\left(\text{T}\right)$ Nothing can be said.

1. $\text{A}\to \text{P},\text{B}\to \text{Q},\text{C}\to \text{R}$
2. $\text{A}\to \text{Q},\text{B}\to \text{P},\text{C}\to \text{R}$
3. $\text{A}\to \text{R},\text{B}\to \text{Q},\text{C}\to \text{P}$
4. $\text{A}\to \text{R},\text{B}\to \text{P},\text{C}\to \text{Q}$

Q. a thin stationary ring of radius 1m has a positive charge 10mc uniformly distributed over it . a particle of mass 0.9gm and having a negative charge of 1mc is placed on the axis at a distance of 1cm from the centre of the ring and released then time period would be?

Q. calculate the time period of a charged particle -q placed on the axis of charged ring , radius R , having linear charge distribution L , where the charged particle is placed at x from centre.[x<<<R]

Q. An electric flux of -6 × 10 to the power -3 Nm*m/C passes normally through a spherical Gaussian surface of radius 10 cm, due to a point charge placed at its centre. a) If the radius of the Gaussian surface is doubled, how much flux would pass through the surface

Q. A particle of mass m and carrying charge -q1 is moving around a charge+q2 along a circular path of radius r. Find period of revolution of the charge q

Q. Two infinite sheets having charge densities ${\sigma }_1$ and ${\sigma }_2$ are placed in two perpendicular planes whose two-dimensional view is shown in the figure. Net electric field at point $\text{P}$ is

1. $\frac{\sqrt{{\sigma }_1^2+{\sigma }_2^2}}{2{ϵ}_0}$
2. $\frac{{\sigma }_1^2+{\sigma }_2^2}{{ϵ}_0}$
3. $\frac{{\sigma }_1^2-{\sigma }_2^2}{2{ϵ}_0}$
4. Data insufficient

Q.

Two parallel plane sheets 1 and 2 carry uniform charge densities ${\sigma }_1$ and ${\sigma }_2$ (see Fig. 20.8). The electric field in the region marked I is $({\sigma }_1>{\sigma }_2)$. (Consider the right direction as the positive direction)

1. $-\frac{({\sigma }_1+{\sigma }_2)}{2{ϵ}_0}$

2. $-\frac{{\sigma }_1}{2{ϵ}_0}$

3. $-\frac{{\sigma }_2}{2{ϵ}_0}$

4. $-\frac{({\sigma }_1-{\sigma }_2)}{2{ϵ}_0}$

Q. A particle of mass m and carrying charge -q1 is moving around a charge +q2 along a circular path of radius r find period of revolution of the charge -q1

Q. Why do the electric field lines move from positive to negative charge??

Q. A 10-cm long rod carries a charge of +50 μC distributed uniformly along its length. Find the magnitude of the electric field at a point 10 cm from both ends of the rod.

Q. Find the direction of electric field at point $\text{P}$ for the uniform line charge distribution of finite length as shown in figure, if line OP is equidistant from both the ends.

1. Along positive $x-$ axis
2. Along negative $x-$ axis
3. Along positive $y-$ axis
4. Along negative $y-$ axis

Q. No tutorial found for a thin stationary ring of radius 1m has a positive charge 10mc uniformly distributed over it . a particle of mass 0.9gm and having a negative charge of 1mc is placed on the axis at a distance of 1cm from the centre of the ring and released then time period of oscillation of particle will be -

Q.

Electric flux through an area dA for an electric field E is given by

1. E/dA

2. E.dA

3. ExdA

4. (E.dA)/q

Q. A rectangular surface of side 10 cm and 15cm is placed inside a uniform electric field of 25V/m, such that normal to the surface makes an angle of 60 with the direction of electric field. Find the flux of electric field through the rectangular surface?

Q.

what is a non uniform electric field?

Q. Two equal positive charges Q are fixed at point (a, 0)&(-a, 0) on the x axis . An opposite charge of -q at rest id released from point (0, a) on the Y axis . The charge -q will - 1) move to infinity 2)move to origin &rest there 3) under go SHM about the origin 4) Execute oscillatory periodic motion but not SHM

Q. A particle of charge -q & mass m moves in a circle of radius r around an infinitely long line charge having linear charge density +λ. Then time period will be--

1. 

2. 

3. 

4. 

Q.

electric flux i flow of electric field means it has direction then it is scalar or vector quantity ?

Q.

A fixed horizontal wire A carrying current of 8 A supports another horizontal wire B carrying current 10 A , hanging in air at a distance 5 cm below the wire A. Considering the direction of current in two wires as same. Find the weight of wire B.

1. 320 N

2. 32 N

3. 3.2 × 10^-5 N

4. 32 × 10^-5 N

Q.

How fast do charges travel? What is the speed of charges?

Q. The correct Maxwell's equation is -

1. $\int \overrightarrow{B}.d\overrightarrow{l}=0$
2. $\int \overrightarrow{B}.d\overrightarrow{A}=0$
3. $\oint \overrightarrow{B}.d\overrightarrow{l}=0$
4. $\oint \overrightarrow{B}.d\overrightarrow{A}=0$

Q. The electric field potential at a point in the space region depends only on x coordinates as $V=-a{x}^3+b$. The space charge density $\rho$(x) is $na{\epsilon }_{0}x$. Find $n$.

Q.

why electric flux is zero when r<R?

Q. Calculate the time period of a charged particle -q placed on the axis of charged ring , radius R , having linear charge distribution L , where the charged particle is placed at x from centre.[x<<

Q.

why the current is called conventional current?