Most Important Selected Qs for JEE AdvancedPhysicsMechanical Properties of Fluids
When a long glass capillary tube of radius 0.015 cm is dipped in a liquid, the liquid rises to a height of 15 cm within it. If the contact angle between the liquid and glass to close to 0^ , the surface tension of the liquid, in milli Newton m ⁻¹ , is [ _ ( liquid ) =900 kgm ⁻³, ~g =10 ~ms ⁻² ] (Give answer in closest integer)
Correct answer
101
Step-by-step solution
Given : Radius of capillary tube, r =0.015 ~cm =15 10⁻⁵ ~mm h =15 ~cm =15 10⁻² ~mm Using, h = 2 ~T gr [ = 0^ =1 ] Surface tension, T= rhpg 2 = 15 10⁻⁵ 15 10⁻² 900 10 2 =101 milli newton m ⁻¹