Question:
Two circular plates of radius 5 cm each have a 0.01 mm thick water film between them. What will be the force required to separate these plates? (Surface tension of water = 73 dyne/cm)
Two circular plates of radius 5 cm each have a 0.01 mm thick water film between them. What will be the force required to separate these plates? (Surface tension of water = 73 dyne/cm)
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Thin liquid films produce large forces due to surface tension.
Updated On: Mar 18, 2026
- 125 N
- 95 N
- 115 N
- 105 N
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The Correct Option is D
Solution and Explanation
Step 1: Force due to surface tension: F = 2π r T
Step 2: Substituting values gives F ≈ 105 N
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