JEE Mains · Physics · STD 11 - Surface tension
- JEE Mains 2025
- Medium
- MCQ
Two liquids A and B have \(\theta_{\mathrm{A}}\) and \(\theta_{\mathrm{B}}\) as contact angles in a capillary tube. If \(K=\cos \theta_A / \cos \theta_B\). then identify the correct statement:
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) K is negative, then liquid A has concave meniscus and liquid \(B\) has convex meniscus
Step-by-step Solution
Detailed explanation
\(\mathrm{k}=\frac{\cos \theta_{\mathrm{A}}}{\cos \theta_{\mathrm{B}}}\)
It is negative when \(\cos \theta_A \& \cos \theta_B\) are of opposite sign. so option (3)
It is negative when \(\cos \theta_A \& \cos \theta_B\) are of opposite sign. so option (3)
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