"A drop of oil placed on the surface of water spreads out. But a drop of water placed on oil contracts to a spherical shape". Why?

Explanation

To understand why a drop of oil spreads on water while a drop of water contracts on oil, we need to analyze the forces at play: adhesive forces and cohesive forces.

### Step-by-Step Solution:

1. **Understanding Adhesive and Cohesive Forces**:
- **Cohesive Forces**: These are the intermolecular forces that act between molecules of the same substance. For example, in water, the cohesive forces are strong due to hydrogen bonding between water molecules.
- **Adhesive Forces**: These are the forces that act between different substances. For example, the forces between oil molecules and water molecules.

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