An electric flux & passes normally through a spherical Gaussian surface due to a point charge placed at the centre.If the radius of the Gaussion surface is doubled how much flux would pass through the surface?
∅
2?
4?
?/2
At any point on the right bisector of an electric dipole
Electric field is zero
Electric field is perpendicular to the dipole
Electric field is parallel to the dipole
None of these
Ic charge is equal to the charge of
1.6*10-19 electrons
6.25*1018 electrons
9*10-9 electron
none of these
For what purpose Gold leaf electroscope is used?
To find the electric field
To find the electric potential
To detect the charge on a body
To find the force between charges.
Two charges exert a force F when kept at distance r between them is air.The distance at which they exert same force in a medium of relative permittivity 4 is
r/4
r/2
4r
2r
Insulted copper spheres of radii 0.1m and 0.15m and having equal charges are connected by a copper wire and separated then
both spheres will have the same charge
smaller sphere will have greater charge.
bigger sphere will have greater greater charge
Charge on either sphere becomes zero.
The radius of hydrogen atom is 5*10-11 m and the charge on electron or proton is of magnitude 1.6*10-11 c. At ground state,the dipole moment of the atom is
8*10-30cm
16*10-30cm
0 cm
4*10-30cm
Three charges +4q,Q and q are placed in a straight line of length l at points 0,l/2,l respectively what should be Q in order to make the net force on q to zero?
-q
-2q
-q/2
+q
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
A charge q is placed at the centre of the line joining two equal charges Q.The system of the three charges will be in equlilibrium if q is equal to
-Q/2
-Q/4
+Q/4
+Q/2
