Question

Calculate the Energy Evolved when 8 Droplets of Water (SURFACE TENSION ==0.072 N/M) of Radius 1/2 mm each combines into a 1 Single Drop.

Answer 1

it is only surface energy which is going to be released

Answer 2

The energy evolved is 9.0478 × 10`7.

Let the number of droplets be = n (Given)

Surface tension of water = 0.072N (Given)

Radius of each droplet r = 1/2 = 5 × 10`4mm (Given)

Since, droplets are combining to form into a bigger droplet, the total energy released will be -

Eloss = 4π ( n - n`2/3) r²T

= 4π ( 8 - 8`2/3) × 5 × 10`4 × 0.072

= 9.0478 × 10`7

Therefore, the energy evolved during the combining into a single drop is 9.0478 × 10`7.