Two soap bubbles combine to form a single bubble. In this process, the change in volume and surface area are respectively V and A. If p is the atmospheric pressure, and T is the surface tension of the soap solution, the following relation is true. |
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a) |
4pV + 3TA = 0 |
b) |
3pV - 4 TA = 0 |
c) |
4pV – 3TA = 0 |
d) |
3pV + 4TA = 0 |

Two soap bubbles combine to form a single bubble. In this process, the change in volume and surface area are respectively V and A. If p is the atmospheric pressure, and T is the surface tension of the soap solution, the following relation is true. |
|||||||

a) |
4pV + 3TA = 0 |
b) |
3pV - 4 TA = 0 |
c) |
4pV – 3TA = 0 |
d) |
3pV + 4TA = 0 |

1 Answer

127 votes

**(d)**

Let radii of two soap bubble are a and b respectively and radius of single larger bubble is c .

As excess pressure for a soap bubble is and external pressure p

Now as mass is conserved.

As temperature is constant,

Which in the light of Eqs. (i) and (ii) becomes,

127 votes

127