A soap bubble of radius 1 cm expands into a bubble of radius 2 cm. Calculate the increase in surface energy if the surface tension for soap is 25 dyne/cm.

A soap bubble of radius 1 cm expands into a bubble of radius 2 cm. Cal

1.	A soap bubble of radius 1 cm expands into a bubble of radius 2 cm. Calculate the increase in surface energy if the surface tension for soap is 25 dyne/cm.
Answer» Solution :Surface energy PER UNIT area is equal to surface tension. E = increase in surface area `xx` ST `=4pi(2^(2)-1^(2))xx2.5` =`4pixx3xx2.5` =`1.02xx10^(3)`erg