NEET2019PhysicsMechanical Properties of FluidsActual
A soap bubble having radius of 1   m m is blown from a detergent solution having a surface tension of 2.5 × 10 - 2   N   m - 1 . The pressure inside the bubble equals at a point Z 0 below the free surface of water in a container. Taking g = 10   m   s - 2 , density of water = 10 3   k g   m - 3 , the value of Z 0 is
Options
- A100 c m
- B10 c m
- C1 c m
- D0.5 c m
Correct answer
C. 1 c m
Step-by-step solution
Pressure inside soap bubble is given by, ∆ P = 4 T R Pressure below water surface at depth Z 0 is given by, ∆ P = ρ g Z 0 According to question, ⇒ 4 T R = ρ g Z 0 ⇒ Z 0 = 4 T ρ g = 4 × 2.5 × 10 - 2 10 3 × 10 × 10 - 3 ⇒ Z 0 = 1 100   m ⇒ Z 0 = 1   c m