A clean glass tube of radius 0.40 mm is dipped in water and tilted at 45° to the vertical…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A clean glass tube of radius is dipped in water and tilted at to the vertical. How high, measured straight up, does the water rise? How long is the column of water along the tube? (Surface tension , angle of contact , .)
Need a reminder? The key ideaShow
Capillary rise: , where is the angle of contact. A liquid that wets the tube () rises; one that does not () is pushed down.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Height. .
Step 2. Length. .
Answer: up; along the tube.
Watch out. Surface tension must hold up a column of the same height, so the tilted tube holds a longer column.
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