A uniform meter scale is put on a knife edge at 40 cm mark. It is found that this scale gets balanced when a weight of 20 gf is suspended from the 20 cm mark. Find the weight of meter scale.

Explanation

To solve the problem, we need to analyze the forces acting on the meter scale and apply the principle of moments (torque). Here’s a step-by-step solution:

### Step 1: Identify the system
We have a uniform meter scale (1 meter long) balanced on a knife edge at the 40 cm mark. The center of mass of the meter scale is located at the 50 cm mark.

### Step 2: Define the forces
Let:
- \( m \) = weight of the meter scale (in gf)
...