Electric Field (Discrete and Continuous Charge Distributions)

Assertion: Due to two point charges electric field and electric potential cannot be zero at some point simultaneously.

Reason: Field is a vector quantity and potential is a scalar quantity.

Two point charges $q$ and $2q$ are placed some distance apart. If the electric field at the location of $q$ be $E$, then that at the location of $2q$ will be

The maximum field intensity on the axis of a uniformly charged ring of charge $q$ and radius $R$ will be

Two large circular discs separated by a distance of $0.01 \mathrm{m}$ are connected to a battery via a switch as shown in the figure. Charged oil drops of density $900 \mathrm{kg}{ \mathrm{m}}^{-3}$ are released through a tiny hole at the center of the top disc. Once some oil drops achieve terminal velocity, the switch is closed to apply a voltage of $200 \mathrm{V}$ across the discs. As a result, an oil drop of radius $8\times {10}^{-7} \mathrm{m}$ stops moving vertically and floats between the discs. The number of electrons present in this oil drop is ______.(neglect the buoyancy force, take acceleration due to gravity $=10{ \mathrm{ms}}^{-2}$ and charge on an electron $\left(\mathrm{e}\right)=1.6\times {10}^{-19}\mathrm{C}$)

Infinite number of charges of magnitude $6 \mu \mathrm{C}$ each are lying at $y=2, 4, 8, 16\dots$ metre on $Y$-axis. The value of electric field intensity at point $y=0$ due to these charges will be $a\times {10}^4 \mathrm{N} {\mathrm{C}}^{-1}$, find the value of $a$,

The tracks of three charged particles in a uniform electrostatic field are shown in the figure. Which particle has the highest charge to mass ratio?

If the flux of the electric field through a closed surface is zero then

The constant $\mathrm{k}$ in Coulomb’s law depends on

A metal plates of capacitor of area $0.01 {\mathrm{m}}^2$ carries a charge of $100 \mathrm{\mu C}$. Calculate the outward pull on plate (in newton).

A metallic shpere is placed in a uniform electric field. The line of force follow the path(s) shown in the figure as,

The maximum field intensity on the axis of a uniformly charged ring of charge $q$ and radius $R$ will be

A thin conducting ring of radius $R$ is given a charge $+Q$. The electric field at the centre $O$ of the ring due to the charge on the part $AKB$ of the ring is $E$. The electric field at the centre due to the charge on the part $ACDB$ of the ring is

The tracks of three charged particles in a uniform electrostatic field are shown in the figure. Which particle has the highest charge to mass ratio?

If the flux of the electric field through a closed surface is zero

The constant $\mathrm{k}$ in Coulomb’s law depends on

Two point charges of $20 \mu \mathrm{C}$ and $80 \mu \mathrm{C}$ are $10 \mathrm{cm}$ apart where will the electric field strength be zero on the line joining the charges from $20 \mu \mathrm{C}$ charge

A small metal ball is suspended in an uniform electric field with the help of an insulated thread. If a high energy $\mathrm{X}$-ray beam falls on the ball, then the ball

The electric intensity outside a charged sphere of radius $R$ at a distance $r(r>R)$ is

The minimum strength of a uniform electric field that can tear a conducting neutral thin-walled sphere into two equal parts is known to be $E_0$. Then determine the minimum electric field strength required to tear a sphere of one-fourth of the radius with the same wall thickness.