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Question
Find the surface energy of water kept in a cylindrical vessel of radius 6.0 cm. Surface tension of water = 0.075 J m−2.
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Solution
Given:
Radius of cylindrical vessel, r = 6.0 cm = 0.06 m
Surface tension of water, T = 0.075 J/m2
Area, A = πr2 = π × (0.06)2
Surface energy = T × A
= (0.075) × (3.14) × (0.06)2
= 8.5 × 10−4 J
Therefore, the surface energy of water kept in a cylindrical vessel is 8.5 × 10−4 J.
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