Electric Charge and Field

A point charge of + $12\mu C$  is at a distance 6cm vertically above the centre of a squared of side 12cm as shown in figure. The magnitude of the electric flux through the square will be…………….* 10³ Nm²/C.

A point charge of + $12\mu C$  is at a distance 6cm vertically above the centre of a squared of side 12cm as shown in figure. The magnitude of the electric flux through the square will be…………….× 10³ Nm²/C.

In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius 2.0 * 10^-5m and density 1.2 * 10³ kgm^-3? Take viscosity of liquid = 1.8 * 10^-5 Nsm^-2. (Neglect buoyancy due to air).

A uniformly charged disc of radius R having surface charge density $\sigma$ is placed in the xy plane with its centre at the origin. Find the electric field intensity along the z-axis at a distance Z from origin:-

In the figure, a very large plane sheet of positive charge is shown. P1 and P2 are two points at distance $\mathcal{l}and2\mathcal{l}$  from the charge distribution. If $\sigma$  is the surface charge density, then the magnitude of electric fields E₁ and E₂ at P₁ and P₂ respectively are:

A long cylindrical volume contains a uniformly distributed charge of density $\rho C{m}^{-3}.$  The electric field inside the cylindrical volume at a distance $x=\frac{2{\epsilon }_0}{\rho }m$  from its axis is_________Vm^-1.

Two electric dipoles of dipole moments 1.2 * 10^-30 Cm and 2.4 * 10^-3 Cm are placed in two different uniform electric fields of strengths 5 * 10⁴ NC^-1 and 15 * 10⁴ NC^-1 respectively. The ratio of maximum torque experienced by the electric dipoles will be $\frac{1}{x}.$  The value of x is_______.

Given below are two statements:

Statement I : The electric force changes the speed of the charged particle and hence charges its kinetic energy; whereas the magnetic force does not change like kinetic energy of the charged particle.

Statement II : The electric force accelerates the positively charged particle perpendicular to the direction of electric field. The magnetic force accelerated the moving charged particle along the direction of magnetic field.

In the light of the above statements, chose the most appropriate answer from the option given below

A running fork of frequency 340 Hz resonates in the fundamental mode with a air column of length 125cm in a cylindrical tube closed at one end. When water is slowly poured in it, the minimum height of water required for observing resonance once again is __________cm.

(Velocity of sound in air is 340 ms^-1)

A capacitor C₁ of capacitance $5\mu F$  is charged to a potential of 30V using a battery. The battery is then removed and the charged capacitor is connected to an uncharged capacitor C₂ of capacitance $10\mu F$ as shown in figure. When the switch is closed charge flows between the capacitors. At equilibrium, the charge on the capacitor C₂ is__________   $\mu C.$