Air (density $\rho$ ) is being blown on a soap film (surface tension $T$ ) by a pipe of radius $R$ with its opening right next to the film. The film is deformed and a bubble detaches from the film when the shape of the deformed surface is a hemisphere. Given that the dynamic pressure on the film due to the air blown at speed $v$ is $\frac{1}{2}\rho v^2,$ the speed at which the bubble formed is

• A

  $\sqrt{\frac{T}{\rho R}}$
• B

  $\sqrt{\frac{2T}{\rho R}}$
• C

  $\sqrt{\frac{4T}{\rho R}}$
• Correct answer
  D

  $\sqrt{\frac{8T}{\rho R}}$

Hence, the correct answer is option: 'D'.