Find the electric field and potential at the centre of a square of side d = 10 cm. Four identical charges of `q=2muC` each are kept at the four corners of a square.

Explanation

To find the electric field and potential at the center of a square with side length \( d = 10 \, \text{cm} \) and four identical charges \( q = 2 \, \mu\text{C} \) placed at the corners, we can follow these steps:

### Step 1: Understand the Geometry
The square has a side length \( d = 10 \, \text{cm} = 0.1 \, \text{m} \). The center of the square can be found by drawing the diagonals, which intersect at the center.

### Step 2: Calculate the Distance from the Center to Each Charge
The distance from the center of the square to each corner (where the charges are located) can be calculated using the Pythagorean theorem. Each half of the square's side is \( \frac{d}{2} = 0.05 \, \text{m} \). Thus, the distance \( r \) from the center to a corner is:

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