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प्रश्न
Distinguish between cohesive and adhesive forces.
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उत्तर
| Cohesion Force | Adhesion Force | |
| 1. | The force between the like molecules which hold the liquid together is called ‘cohesive force’. | When the liquid is in contact with a solid, the molecules of these solid and liquid will experience an attractive force which is called ‘adhesive force’. |
| 2. | A strong force of cohesion forms water droplets on any surface. | A strong adhesion force causes the liquid to spread all over the surface. |
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[Take surface tension of water T = 7.3 × 10-2 Nm-1, angle of contact = 0, g = 10 ms-2 and density of water = 1.0 × 103 kgm-3]
