Angle of contactθ cosθ=TLATSA−TSL when water is on a waxy or oily surface TSA<TSLcosθ is negative i.e., 90∘<θ<180∘ i.e., angle of contact θ increases And for θ>90∘ liquid level in capillary tube fall. i.e., h decreases
Wax is coated on the inner wall of a capillary tube and the tube is then dipped in water. Then, compared to the unwaxed capillary, the angle of contact θ and the height h upto which water rises change. These changes are :
Held on 23 Apr 2013 · Verified 6 Jul 2026.
θ increases and h also increases
θ decreases and h also decreases
θ increases and h decreases
θ decreases and h increases
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