Concepts Of Physics MCQ Edition [Volume 1]PhysicsSome Mechanical Properties of Matter
Determine the excess pressure inside an air bubble of radius 4 mm formed within a tank of water. The surface tension of water is given as 0.076 N/m .
Options
- A19 N/m ^2
- B152 N/m ^2
- C76 N/m ^2
- D38 N/m ^2
Correct answer
D. 38 N/m ^2
Step-by-step solution
The excess pressure inside an air bubble formed within a liquid is given by the formula: P = 2T R where T is the surface tension of the liquid and R is the radius of the bubble. Given: T = 0.076 N/m R = 4 mm = 4 10⁻³ m Substituting the values into the formula: P = 2 0.076 4 10⁻³ P = 0.152 4 10⁻³ P = 38 N/m ^2