The charges on two spheres are +7mC and –5mC respectively. They experience a force F. If each of them is given an additional charge of –2mC, the new force of attraction will be
Two balls carrying charges - and +8 attract each other with a force F. If a charge of -3 is added to both the balls, then the force between then will become
A. 2F
B. F/2
C. F
D. zero
Two point charges q1 and q2 are located at points (a, 0, 0) and (0, b, 0) respectively. Find the electric field due to both these charges at the point (0, 0, c).
Three charges each equal to 2 μC are placed at the corners of an equilateral triangle. If force between any two charges is 2F, then the net force on either will be:
Derive an expression for electric field of a dipole at a point on the equatorial plane of the dipole. How does the field vary at large distances?
Two-point charges 2μC and 4μC are placed 2 cm apart. The ratio of the Coulomb’s force experienced by them is
(A) 1: 2
(B) 2: 1
(C) 1: 1
(D) 4: 1
A point charge +Q is placed in the vicinity of a conducting surface. Draw the electric field lines between the surface and the charge.
State which of the two a capacitor or an inductor, tends to become SHORT when the frequency of the applied alternating voltage has a high value.
Plot a graph showing the variation of current I versus resistance R, connected to a cell of emf E and internal resistance r.
What is the value of the angle between the vectors and for which the potential energy of an electric dipole of dipole moment , kept in an external electric field , has the maximum value.
Why is choke coil needed in the use of fluorescent tubes with ac mains ?
For any charge configuration, equipotential surface through a point is normal to the electric field. Justify.
When electrons drift in a metal from lower to higher potential, does it mean that all the free electrons of the metal are moving in the same direction ?