Two vertical rods of equal lengths, one of steel and the other of copper, are suspended from the ceiling at a distance `l` apart and are connected rigidly to a rigid horizontal bar at their lower ends. If `A_(S)` and `A_(C)` be their respective cross-sectional areas, and `Y_(S)` and `Y_(C)`,their respective Young's moduli of elasticities, where should a vertical force `F` be applied to the horizontal bar in order that the bar remains horizontal?

Explanation

To solve the problem, we need to determine where to apply a vertical force \( F \) on a horizontal bar connected to two vertical rods made of steel and copper, such that the bar remains horizontal. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Setup
We have two vertical rods (one steel and one copper) of equal lengths suspended from the ceiling. They are connected at their lower ends to a rigid horizontal bar. The rods are at a distance \( l \) apart.

### Step 2: Define Variables
Let:
- \( A_S \) = Cross-sectional area of the steel rod
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