Calculate the Pressure Inside the Raindrop. - Physics


A raindrop of diameter 4 mm is about to fall on the ground. Calculate the pressure inside the raindrop. [Surface tension of water T = 0.072 N/m, atmospheric pressure = 1.013 x 105 N/m2 ]




T = 0.072 N/m,

d = 4mm ∴ r = 2 * 10-3 m,

P= 1.013 * 105 N/m2

To find: Pressure inside the raindrop (Pi)

Formula: Pi = Po + 2T/r

Calculation: From formula,





The pressure inside the raindrop is 1.01372 * 105 Pa.

Concept: Surface Tension
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2014-2015 (October)


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