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Question
When water droplets merge to form a bigger drop
Options
energy is liberated
energy is absorbed
energy is neither liberated nor absorbed
energy may either be liberated or absorbed depending on the nature of the liquid.
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Solution
As the water droplets merge to form a single droplet, the surface area decreases. With this decrease in surface area, the surface energy of the resulting drop also decreases. Therefore, extra energy must be liberated from the drop in accordance with the conservation of energy.
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