A long horizontal rigidly supported wire carriers a current `i_a = 96 A`. Directly above it and parallel to it at a distance, another wire of 0.144 N weight per metre carries a current `i_b = 24` A, in a direction opposite to that of `i_a` If the upper wire is to float in air due to magnetic repulsion, what is its distance (in mm) from the lower wire ?

Explanation

To solve the problem, we need to find the distance \( D \) between the two wires such that the magnetic repulsion force equals the weight of the upper wire. Let's break this down step by step.

### Step 1: Understand the Forces Acting on the Upper Wire
The upper wire experiences two forces:
1. The downward gravitational force (weight) due to its mass.
2. The upward magnetic force due to the current in the lower wire.

### Step 2: Calculate the Weight of the Upper Wire
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