Calculate the Pressure Inside the Raindrop. - Physics

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Numerical

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 ]

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Solution

Given:

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,

`P_i=1.013xx10^5+(2xx0.072)/(2xx10^(-3))`

`P_i=1.013xx10^5+0.072xx10^3`

    `=1.013xx10^5+0.00072xx10^5`

`thereforeP_i=1.01372xx10^5Pa`

The pressure inside the raindrop is 1.01372 * 105 Pa.

Concept: Surface Tension
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2014-2015 (October)

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