An isolated metal sphere of radius R is given a charge q. its potential energy will be
q2/ 4π∈0R
q/ 4π∈0R
q/ 8π∈0R
q2/ 8π∈0R
The electric potential v as a function of distance x is metres is given by V= (5x2-10x-9) volt. The value of electric filed at x= 1m would be
20 v/m
6 v/m
zero
11 v/m
A charge q is located at the centre of a cube.The electric flux through any one face of the cube is
q/εo
q/2εo
q/4εo
q/6εo
A charged particle of mass 8 gm remains stationary on a vertical electric field.104KN/c.The amount of charge is
7.8×10-9 c
8×10-10c
8×1019c
8×10-19c
A parallel plate capacitor is charged and the charging battery is then disconnected. If the plates of the capacitor are moved farther apart by means of insulating handles.
The charge on the capacitor increases
The voltage across the plates increases
The capacitance increases
The charge on the capacitor decreases
Two spherical conductors B and c of equal radii and carrying equal charge on them repel each other with a force F when kept apart at some distance.A third spherical conductor having some redius as that of B but uncharged is brought in contact with B and then with C and removed away from both.The new force of repulsion between B and C
F/4
3F/4
F/8
3F/8
Inside a hollow charged spherical conductor the potential
Is constant
Varies directly ad the distance from the centre
varies inversely as the distance from the centre
varies inversely as the square of the distance from the centre.
An Electric dipole when placed in a uniform electric field E will have minimum potential energy if the dipole moment makes an angle with E which is given by
0 rad
π rad
π/2 rad
3π/2 rad
Three capacitors of capacitance 3μF, 9μF and 18 μF are connected first in series and then in parallel. The ratio of the equivalent capacities in the two cases is
1:15
15:1
1:1
1:2
The electric field at a certain point is 10NC-1.The electric lines of force crossing unit area around the point at right angles to it is
εo
1/εo
10
10/εo
