Calculation of Potential at the Centre of Two Charges

To calculate the potential at the centre of two charges, we need to consider the formula of electric potential due to point charges. The formula is as follows:

V = kq/r

where V is the electric potential, k is the Coulomb constant, q is the charge, and r is the distance between the two charges.

Given Information

- The charges are placed 0.35 cm apart
- The charges are 20uC and -20uC

Calculation of Electric Potential

First, we need to calculate the distance between the two charges. As the charges are placed 0.35 cm apart, the distance between them is 0.35/2 = 0.175 cm.

Now, we can use the above formula to calculate the electric potential at the centre of the line joining the two charges.

V = kq/r
V = (9 x 10^9 Nm^2/C^2) x (20 x 10^-6 C) / (0.175 x 10^-2 m)
V = 205.7 V

Therefore, the potential at the centre of the line joining the two charges is 205.7 V.

Explanation

The electric potential due to a point charge is the amount of work required to move a unit positive charge from infinity to a point in the vicinity of the charge. The electric potential at any point due to two or more point charges is the algebraic sum of the electric potentials due to each charge.

In this case, we have two point charges, 20uC and -20uC, placed 0.35 cm apart. As the charges are of equal magnitude but opposite in sign, the net charge is zero. Therefore, the potential at infinity is zero.

The electric potential at the centre of the line joining the two charges is the sum of the electric potentials due to the two charges. The distance between the charges is half of the given distance, as we are calculating the potential at the centre. Using the formula, we can calculate the electric potential at the centre.

The result shows that the potential at the centre of the line joining the two charges is positive, which means that a positive charge placed at that point would experience a repulsive force from both charges. Similarly, a negative charge placed at that point would experience an attractive force from both charges.

Zero