Question

If the diameter of a soap bubble is 10mm and it's surface tension is 0.04n/m, find the excess pressure inside the bubble

Answer 1

Given :

The diameter of the soap bubble = 10 mm

We know that

$1 \: mm \: = \: 1 \times {10}^{ - 3} \: m$

So ,

5 mm :

$5 \: mm \: = \: 5 \times {10}^{ - 3} m$

Surface Tension of the bubble = 0.04 n/m

To Find : The excess pressure inside the bubble.

Solution :

The excess pressure on the soap bubble is given by =

4 times the surface Tension divided by radius

= 4 × Surface Tension ÷ Radius

= 4 × 0.04 ÷ 5 × 10^-3 N/m²

= 32 N/m²

The required excess pressure on the soap bubble is 32 N/m²