A convex lens focusses an object 10 cm from it on a screen placed 10 cm away from it. A glass plate `(mu=1.5)` of thickenss 1.5 cm is inserted between the lens and the screen. Where should the object be placed so that its image is again focussed on the screen?

Explanation

To solve the problem step by step, we will analyze the situation before and after the insertion of the glass plate.

### Step 1: Analyze the initial situation without the glass plate
1. **Given Data**:
- Object distance (u) = -10 cm (the negative sign indicates that the object is on the same side as the incoming light).
- Image distance (v) = +10 cm (the positive sign indicates that the image is on the opposite side of the lens).

2. **Using the Lens Formula**:
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