As we know that for a soup bubble, the excess press = 4T/r

External pressure is p_{0}

_{}

Applying conservation of mass

µ_{a} + µ_{b} = µ_{c}

_{}

Since, temp is constant

i.e., T_{a} = T_{b }= T_{c},

so the above expression reduces to

p_{a} v_{a} + p_{b}v_{b} = p_{c} v_{c}

with the help of equation (1), we have