Field Lines in Different Scenarios

Q. A spherical conductor of radius 10cm has a charge of 3.2 * 10^-7 C distributed uniformly. What is the magnitude of electric field at a point 15 cm from the centre of the sphere ??

Q. The electric field at 20 cm from the centre of a uniformly charged non conducting sphere of radius 10 cm is E. Then at a dis†an ce 5 cm from the centre it will be (1) 16E (2)4E (3) 2E (4) Zero

Q. A sphere of radius r has electric charge uniformly distributed in its entire volume. At a dis†an ce d from the centre inside the sphere (d≤≤ r) the electric field intensity is directly proportional to (1) 1/d (2)1/d2 (3)d(4)d

Q. The electric field due to charged circular arc shown in the figure at centre O is

Q. two plane sheets of charge densities +σ & -σ are kept in air . what are the electricfield intensities at points A&B

Q. Find the electric field at the centre of a uniformly charged SOLID HEMISPHERE with volume charge density rho.

Q. 8. S1, S2, S3 three concentric spherical shells as, shown in the figure. S1 and S2 have charge 4Q and 8Q respectively whereas S3 is uncharged. Find the ratio of the flux passing through S1 to that through S3

Q. For a finite line charge, the net electric field at the non-axial point $\text{P}$ is directed toward the line $\text{PQ}$ where $\text{PQ}$ makes an angle $\theta$ with the axis of line charge. Find the value of $\theta$.

1. ${\tan }^{-1}\left(10\right)$
2. ${\tan }^{-1}\left(2\right)$
3. ${\tan }^{-1}\left(14\right)$
4. ${\tan }^{-1}\left(26\right)$

Q. A non conducting sphere of radius R has a spherical cavity of radius R/2 as shown .the solid part of sphere has a uniform vol. Charge density p. Find magnitude and direction of electric field at a pt a) O b) A ( O IS AT CENTRE, A IS AT SURFACE OF SPHERE OF RADIUS R)

Q. There are two concentric hollow conducting spherical shells of radii r and R (R>r). The charge on the outer shell is Q. What charge should be given to the inner shell, so that the potential at a point P , at a distance 2R from the common centre, is zero.

Q. A charge $Q$ is kept at the corner of a cube. If the net flux through the cube is $\varphi$, the electric flux passing through one of those faces not touching the charge will be

1. $\frac{\varphi }{3}$
2. $\frac{\varphi }{6}$
3. $\frac{\varphi }{4}$
4. $\frac{\varphi }{8}$

Q. 66. The magnitude of the average electric field normally present in the atmosphere just above the surface of the earth is about 150 N/C , directed inward towards the centre of the earth .This gives the total net surface charge carried by the earth to be ??

Q. An electrostatic field line leaves at angle $\alpha$ from point charge $+q_1$, and connects with point charge $–q_2$ at angle $\beta$. Find the ratio $\frac{q_1}{q_2}$ (Given : $\alpha ={60}^{\circ },\beta ={90}^{\circ }$).

1. $\frac{1}{2}$
2. $\frac{2}{1}$
3. $\frac{3}{4}$
4. None of these

Q. The electric field at a distance $\frac{3R}{2}$ from the centre of a charged spherical shell of radius $R$ is $E$. The electric field at a distance $\frac{R}{2}$ from the centre of spherical shell is

1. $2E$
2. $\frac{2E}{9}$
3. $\frac{E}{3}$
4. Zero

Q. In the given figure, net magnetic field at $O$ will be

1. $\frac{2{\mu }_{o}I}{3\pi a}\sqrt{4-{\pi }^2}$
2. $\frac{{\mu }_{o}I}{3\pi a}\sqrt{4+{\pi }^2}$
3. $\frac{4{\mu }_{o}I}{3\pi a}\sqrt{4-{\pi }^2}$
4. $\frac{{\mu }_{o}I}{3\pi a}\sqrt{4-{\pi }^2}$

Q. A sphere of radius R has charge q uniformly distributed inside it. At what minimum distance from its surface the electric potential is half of the electric potential at the centre.

Q. A small spherical portion has been removed from a solid sphere having a charge distribution uniformly in its volume. The electric field inside the emptied space is (1) Zero everywhere (2) Non-zero and uniform (3)non-uniform(4) Zero only at its centre

Q. .A hemisphere is uniformly charged positively. The electric field ata point on a diameter away from the centre is directed(a) perpendicular to the diameter(b) parallel to the diameter(c) at an angle tilted towards the diameter(d) at an angle tilted away from the diameter

Q. Figure shows a solid conducting sphere of radius 1 m, enclosed by a metallic shell of radius 3 m such that their centres coincide. If outer shell is given a chargeof 6 uC and inner sphere is earthed, find magnitude charge on the surface of inner shell (1) 2 uC(2) 1 uC(3) 6 uC() 4 HC

Q. There is non conducting sphere og radius R which is uniformly charged. If smaller concentric sphere of radius R/2 is removed. The electric field inside the cavity is
(1)Zero
(2)Non zero and uniform
(3)Non zero and non uniform
(4)Data is unsufficient

Q. Two point charges $+10\text{nC}$ and $-10\text{nC}$ are separated by a distance of $6\text{cm}$. Find the electric flux hrough a circle of radius $4\text{cm}$ placed with its centre coinciding with the mid - point of line joining the two charges in the perpendicular plane as shown in the figure.

1. $442.4{\text{N-m}}^2/\text{C}$
2. $542.2{\text{N-m}}^2/\text{C}$
3. $642{\text{N-m}}^2/\text{C}$
4. $742{\text{N-m}}^2/\text{C}$

Q.

The field lines for single positive charge are:

1. Parallel

2. Circular

3. Radiating inwards

4. Radiating outwards

Q. For a finite line charge, find the electric field at the non-axial point $\text{P}$, perpendicular to axis of line charge.

1. $44.6\text{N/C}$
2. $57.6\text{N/C}$
3. $60.6\text{N/C}$
4. $63.6\text{N/C}$

Q. wo identical infinite positive line charges areplaced along the lines X ta in the x-y plane. Apositive point charge placed at origin is restrictedto move along x-axis. Its equilibrium isx-ax=+a(1) Unstable(2) Stable3 Neutral(4) None of these

Q. ABC is an equilateral triangle. Charges +placed at each corner. The electricat the centroid of triangle will beq arefield intensity

Q. ABCDEF is a regular hexagon of side a charges +Q each are placed at A, B andC -Q are placed at D, E, F taken in order .point O lies at the centre of hexagon . The electric field on the line passing through piont O and perpendicular to the plane of hexagon at a distance x from O , where x>>>a, is

Q.

The field lines for single negative charge are:

1. Spheres concentric with charge

2. Radiated inwards

3. Parallel

4. Radiating outwards

Q. Find the electric field vector at the centre of a uniformly charged hemispherical shell of surface charge density sigma using the relation sigma = dq/2(pi)rdr

Q. Which of the following correctly represents the electric field lines for a spherical conductor having a spherical cavity with a charge $Q$ (not at the center) ?

1. 
2. 
3. 
4. 

Q. A thin ring of radius r made up of a conducting material having charge q .Find the increase in the tension the ring if a point charge Q is placed at centre of ring 1) Qq/8π²ε_0r² 2)Qq/4π r²ε_0 3)Qq/8π r²ε_0 4)Q/16π²r²ε_{