Frequent Electrostatics Questions

A disk of radius r,mass m which has a charge q distributed uniformly over it is rotating in a magnetic field B about it's axis with an angular speed ω.Find the ratio of magnetic moment and angular momentum. ...

A circular loop of radius R carries a current I.Another circular loop of radius r(<<R) carries a current i and is placed at the centre of the larger loop.The planes of the two circles are at right angle to each other.Fi ...

The magnetic field existing in a region is given by B=B0(1+x/l)k→.A square loop of edge l and carrying a current i,is placed with it's edges parallel to the x-y axes.Find the magnitude of the net magnetic force experienced ...

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a battrry of emf 10V and internal resistance 0.5 ohms is connected across a variable resistance R. What is the value of R for which the power delivered in it is maximum? ...

What is the meaning of μμC? ...

two conducting spheres of radii r1 and r2 have charge q1 and q2 respectively.after bringing them in contact,what happens to the energy of the system? a)no change b)increase if q1r2≠q2r1 c)decrease always d)decrease if q1r2â ...

A parallel plate capacitor of capacitance C is connected to a battery and is charged to a potential difference V. Another capacitor of capacitance 2C is similarly charged to a potential difference 2V. The charging battery is ...

Four point charges each of charge +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 S.the system of charges and planar film are in equilibrium.Then find a ...

{Shastras Q-21} a point charge q is brought from infinity and is placed at the center of a conducting neutral spherical shell of inner radius 'a' and outer radius 'b', then work done by external agent is. A}0 B}kq2/2b C}kq2/2 ...

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Condenser A has a capacity of 15 when it is filled with a medium of dielectric constant 15. Another condenser B has a capacity 1 with air between the plates. Both are charged separately by a battery of 100V. After charging, b ...

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

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) ...

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. ...

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 ...

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. ...

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

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 ...

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 ...

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 ...