Physics Electrostatic Potential and Capacitance

Four metallic plates, each with a surface area A, are placed at a distance d from each other as shown in the figure. If points A and B is connected with a battery of emf V, then the charge on the plate a will be   

A cube of side a has charge q at two diagonally opposite vertices as shown in the figure. The net electric potential at the centre of the cube will be

 

If q₁ + q₂ = 3q, then the value of the q₁/q₂, for which the force of repulsion between q₁ and q₂ is maximum is

A capacitor of 20 μF is charged to 500 volt and a capacitor 10μF is charged to 200 volt and connected. Then after connecting both of them, the common potential for each will be :–

Three charges Q,(+q) and (+q) are placed at the vertices of an equilateral triangle of side ℓ as shown in the figure. If the net electrostatic energy of the system is zero, then Q is equal to :-

 

A positive charge is moved from low potential point A to a high potential point B. Then the electric potential energy

Two waves of wavelength 50 cm and 51 cm produced 12 beats per second. The velocity of sound is

A parallel plate capacitor is charged and then charging battery is disconnected. If the plates are now pulled apart with insulated handles

Energy stored in circuit 1 is E. If capacitors in circuit 1 and circuit 2 are connected in parallel as shown, the energy stored becomes $\frac{xE}{6}$ , find x.

Potential due to electric dipole on axial position at distance r from dipole is proportional to (assume r >> length of dipole)