Calculation of Electric Field Intensity at the Middle Point

To calculate the magnitude of the electric field intensity at the middle point of the line joining the two charges, we can use the principle of superposition. This principle states that the total electric field at any point is the vector sum of the electric fields produced by each individual charge.

Given:
- Charge 1 (q1) = 0.01 microcoulomb
- Charge 2 (q2) = -0.01 microcoulomb

Step 1: Calculating the Distance between the Charges
Since the charges are placed apart in vacuum, we need to find the distance between them. Let's assume this distance to be 'd'.

Step 2: Calculating the Electric Field Intensity due to Charge 1 at the Middle Point
The electric field intensity due to charge 1 at the middle point can be calculated using Coulomb's law:

E1 = (1 / (4πε₀)) * (q1 / r₁²)

Where ε₀ is the permittivity of vacuum, q1 is charge 1, and r₁ is the distance between charge 1 and the middle point.

Step 3: Calculating the Electric Field Intensity due to Charge 2 at the Middle Point
Similarly, the electric field intensity due to charge 2 at the middle point can be calculated as:

E2 = (1 / (4πε₀)) * (q2 / r₂²)

Where q2 is charge 2 and r₂ is the distance between charge 2 and the middle point.

Step 4: Calculating the Total Electric Field at the Middle Point
Since electric fields are vector quantities, we need to consider both the magnitudes and directions of the electric fields due to each charge. As charge 2 is negative, the direction of its electric field will be opposite to that of charge 1.

The total electric field at the middle point is given by:

E_total = E1 + E2

Step 5: Direction of the Electric Field at the Middle Point
Since charge 1 and charge 2 have opposite signs, their electric fields will be in opposite directions. Therefore, the direction of the electric field at the middle point will be from charge 2 towards charge 1.

Final Answer:
The magnitude of the electric field intensity at the middle point of the line joining the two charges can be calculated by following the above steps. The direction of the electric field will be from charge 2 towards charge 1.