Question

Water rises in a vertical capillary tube up to $2\sqrt{2}\text{cm}$. If the tube is inclined at an angle ${\theta }^{\circ }$, the length of water risen in the tube is $4\text{cm}$. Find the value of $\theta$.

• A. ${30}^{\circ }$
• B. ${45}^{\circ }$
• C. ${60}^{\circ }$
• D. ${37}^{\circ }$

Answer 1

The correct option is B ${45}^{\circ }$


We know,
The vertical height of the liquid column remains constant even after the tube is inclined at an angle.
So,
$L\cos \theta =h$
$\Rightarrow \cos \theta =\frac{h}{L}=\frac{2\sqrt{2}}{4}=\frac{1}{\sqrt{2}}$
$\therefore \theta ={45}^{\circ }$