JEE Main2017PhysicsMathematics in PhysicsActual
The following observations were taken for determining surface tension T of water by capillary method: diameter of capillary, D = 1.25 × 10 - 2 m rise of water, h = 1.45 × 10 - 2 m Using g = 9.80 m s - 2 and the simplified relation T = r h g 2 × 10 3 N m - 1 the possible error in surface tension is closest to:
Options
- A10 %
- B0 . 15 %
- C1 . 5 %
- D2 . 4 %
Correct answer
C. 1 . 5 %
Step-by-step solution
Percentage error in surface tension ∆ T T = ∆ r r + ∆ h h ∆ r r = ∆ D D = 0.01 1 .25 ∆ h h = 0.01 1.45 ∴ %   e r r o r   i n   T = ∆ T T × 100 = 0.01 1.25 + 0.01 1.45 × 100 = 1.489 ≈ 1.5