Recently Active Electricity And Magnetism Questions

why does potential drop across a capacitor????? ...

Determine the capacitance of a system consisting of a metal ball of radius a and an infinite conducting plane separated from the centre of the ball by the distance b if b>>a. ...

An electric dipole is placed in an electric field generated by a point charge a) The net electric force on the dipole must be zero b) The net electric force on the dipole may be zero c) The torque on the dipole due to the fie ...

The capacity of a parallel plate condenser is . If a dielectric of relative permitivity and thickness equal to one fourth the plate separation is placed between the plates, then its capacity becomes C. The value of will be a) ...

A sphere of 4 cm radius is suspended within a hollow sphere of 6 cm radius. The inner sphere is charged to a potential 3 e.s.u. When the outer sphere is earthed. The charge on the inner sphere is a) 54 e.s.u. b) frac{1}{4}, e ...

An unknown cell balances 300 cm of wire in a potentiometer circuit, but the balance length reduces to 280 cm when a resistance of 28 ohm is added in parallel with the cell.A standard cell of emf 1.1V balances 220 cm on the sa ...

Three concentric metallic spheres A, B and C have radii a, b and c (a<b<c) and surface charge densities on them are sigma ,,-sigma and sigma respectively. The valves of {{V}_{A}} and {{V}_{B}} will be *Image* a) frac{si ...

Two metal pieces having a potential difference of 800 V are 0.02 m apart horizontally. A particle of mass 1.96 X 10–15 kg is suspended in equilibrium between the plates. If e is the elementary charge, then charge on the par ...

A charge Q is distributed over two concentric hollow spheres of radii r and (R>r) such that the surface densities are equal.The potential at the common centre a) frac{Q({{R}^{2}}+{{r}^{2}})}{4pi {{varepsilon }_{0}}(R+r)} b ...

A solid conducting sphere having a charge Q is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the ...

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a thin half ring of radius R=20cm is uniformly charged with total charge q=0.70nC. find the magnitude of the electric field strength at the carvature centre of the half ring. ...

Q) One end of a horizontal thick wire of length 2L and radius 2R is welded to an end of another horizontal thin copper wire of length L and radius R.When the arrangement is stretched by applying forces at two ends, the ratio ...

*Image* Calculate EQ capcitance . please solve ...

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*Image* What's the difference between (c) and (d)? ...

A charged drop of oil of radius 2.76μm and density 920kg/m3 is held stationary in a vertically downward electric field of 1.65*106N/C.(i).Find the magnitude and sign of the charge on the drop.(ii) If the drop captures two el ...

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two point charges +4q and+q are placed at a distance L apart. a third charged particle is so placed that all the three charges are in equilibrium. find the location, magnitude and nature of third charge. ...

Two particles A and B each having a charge Q are placed ata a distance d apart.Where should a paricle of charge q be placed on the perpendicular bisector of AB so that it experinces maximum force?What is the magnitude of this ...

Two particles A and B each carrying a charge Q are held fixed with a separation d between them.A particle C having mass m and charge q is kept at the middle point of line AB(a)if it is displaced through a distance x perpendic ...

Four point charges each of +q are rigidly fixed at the four corners of a square planar soap film of side 'a'.The surface tension of the soap film is T.The system of charges and the planar film are in equilibrium and a=k[q2/T] ...

*Image* How to do di type of sums? ...

What is the capacitance of a capacitor having plates of area A1 & A2 at a distance d? Please post explanation as well. ...

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Assertion: In series combination, charges on two capacitors are always equal. Reason: If charges are same, the total potential difference applied across two capacitors will be distributed in inverse ratio of capacities. ...

Assertion: Electric field produced by a variable magnetic field can't exert a force on a charged particle. Reason: This electric field is non-conservative in nature. ...