AP EAMCET202316 May 2023Evening ShiftPhysicsMechanical Properties of FluidsActual
A capillary tube of radius 0.1 ~mm is dipped in water. The water rises to a height of 2 ~cm in the tube. If the surface tension of water is 0.072 Nm ⁻¹ , the contact angle between water and wall of the tube is
Options
- A= ⁻¹ ( 1 3.6 )
- B= ⁻¹ ( 1 7.2 )
- C= ⁻¹ ( 1 1.8 )
- D= ⁻¹ ( 1 6.2 )
Correct answer
B. = ⁻¹ ( 1 7.2 )
Step-by-step solution
Radius of capillary tube, r =0.1 ~mm =0.1 10⁻³ ~m Height of water rises, h =2 ~cm =02 ~m Surface tension, T=0.072 ~N / m Rise in water is given by aligned & h = 2 ~T g r & = h gr 2 ~T & = 2 10⁻² 10^3 10 0.1 10⁻³ 2 0.072 & = ⁻¹ ( 1 7.2 ) aligned