Electric Field and Potential Physics - Electric Field and Potential

Consider the situation of figure. The work done in taking a point charge from P to A is W_A, from P to B is W_B and from P to C is W_C.

1. W_A < W_B < W_C
2. W_A > W_B > W_C
3. W_A = W_B = W_C
4. None of these.

If a body is charged by rubbing it, its weight

1. Remains precisely constant.
2. Increases slightly.
3. Decreases slightly.
4. May increase slightly or may decrease slightly.

The electric potential decreases uniformly from 120V to 80V as one moves on the x-axis from x = -1cm to x = + 1cm. The electric field at the origin.

1. Must be equal to 20Vcm^-1
2. May be equal to 20Vcm^-1
3. May be greater than 20Vcm^-1
4. May be lees than 20Vcm^-1

Figure, shows some of the electric field lines corresponding to an electric field. The figure suggests that,

1. E_A > E₈ > E_e
2. E_A = E_B = E_e
3. E_A = E_c > E_B
4. E_A = E_c < E_B.

Two charged particles having charge 2.0 × 10^-8C each are joined by an insulating string of length 1m and the system is kept on a smooth horizontal table. Find the tension in the string.

NaCl molecule is bound due to the electric force between the sodium and the chlorine ions when one electron. of sodium is transferred to chlorine. Taking the separation between the ions to be 2.75 × 10cm, find the force of attraction between them· State the assumptions (if any) that you have made.

A sample of HCI gas is placed in an electric field of 2.5 × 10⁴NC^-1. The dipole moment of each HCI molecule is 3.4 × 10^-30Cm. Find the maximum torque that can act on a molecule.

Two charged particles are placed at a distance 1.0cm apart. What is the minimum possible magnitude of the electric force acting on each charge?

The charge on a proton is +1.6 × 10^-19C and that on an electron is -1.6 × 10^-19C. Does it mean that the electron has a charge 3.2 × 10^-19C less than the charge of a proton?

A point charge produces an electric field of magnitude 5.0NC^-1 at a distance of 40cm from it. What is the magnitude of the charge?

Consider a gold nucleus to be a sphere of radius 6.9 fermi in which protons and neutrons are distributed. Find the force of repulsion between two protons situated at largest separation. Why do these protons not fly apart under this repulsion?

Can two equipotential surfaces cut each other?

When a charged comb is brought near a small piece of paper, it attracts the piece. Does the paper become charged when the comb is brought near it?

The number of electrons in an insulator is of the same order as the number of electrons in a conductor. What is then the basic difference between a conductor and an insulator?

A particle having a charge of 2.0 × 10^-4C is placed directly below and at a separation of 10cm from the bob of a simple pendulum at rest. The mass of the bob is 100g. What charge should the bob be given so that the string becomes loose?

Suppose the second charge in the previous problem is -1.0 × 10^-6C. Locate the position where a third charge will not experience a net force.

Some equipotential surfaces are shown in figure. What can you say about the magnitude and the direction of the electric field?

Two identical pith balls are charged by rubbing against each other. They are suspended from a horizontal rod through two strings of length 20cm each, the separation between the suspension points being 5cm. In equilibrium, the separation between the balls is 3cm. Find the mass of each ball and the tension in the strings. The charge on each ball has a magnitude 2.0 × 10^-8C.

A particle A having a charge of 2.0 × 10^-6C and a mass of 100g is placed at the bottom of a smooth inclined plane of inclination 30^°. Where should another particle B, having same charge and mass, be placed on the incline so that it may remain in equilibrium?