JEE Main202622 January 2026Evening ShiftPhysicsMechanical Properties of FluidsActual
When a part of a straight capillary tube is placed vertically in a liquid, the liquid raises upto certain height h . If the inner radius of the capillary tube, density of the liquid and surface tension of the liquid decrease by 1 % each, then the height of the liquid in the tube will change by % .
Options
- A+1
- B-3
- C+3
- D-1
Correct answer
A. +1
Step-by-step solution
Capillary height formula: h = 2 g r When radius, density, and surface tension each decrease by 1%: r' = 0.99r , ' = 0.99 , ' = 0.99 New height: h' = 2(0.99 ) (0.99 ) g (0.99r) = h 0.99 0.99 0.99 = h 1 0.99 = h 1.0101... Percentage change: (1.0101 - 1) 100 +1.01 % , which rounds to +1%.