Two long parallel wires are placed vertically, 10cm apart. One of them carries a current of 20A and other carries a current of 25A. Both the currents flow in the upward direction. A third wire carrying a current of 5A flowing downward is placed between the two parallel wires in such a way that its distance from the wire carrying current 20A is 6 cm. Calculate the force per unit length experienced by the third wire.

Explanation

To solve the problem, we need to calculate the force per unit length experienced by the third wire due to the magnetic fields created by the first two wires. Here’s the step-by-step solution:

### Step 1: Identify the Parameters
- Distance between the two wires (d) = 10 cm = 0.1 m
- Current in wire 1 (I1) = 20 A (upward)
- Current in wire 2 (I2) = 25 A (upward)
- Current in wire 3 (I3) = 5 A (downward)
- Distance from wire 1 to wire 3 (d1) = 6 cm = 0.06 m
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