THE PRACTICE STUDIO
Go slowly. Ask why. Make it yours.
PRACTICE / Capillarity
How high does the liquid climb?
A wetting liquid has surface tension 0.050 N/m and density 1000 kg/m³. It rises in a tube of radius 0.50 mm with contact angle zero.
Find the capillary rise.
Organize the givens & assumptions
- γ = 0.050 N/m
- ρ = 1000 kg/m³
- r = 0.00050 m
- cos θ = 1
g = 10 m/s²; narrow circular tube, complete wetting, static rise, large reservoir and negligible meniscus volume.
Study with a tutor prompt
Copy this into your AI assistant, then describe where you got stuck. It asks the tutor to coach you one step at a time. Check its reasoning against the lesson.
Opening this prompt marks this practice attempt as assisted.
Problem: How high does the liquid climb? A wetting liquid has surface tension 0.050 N/m and density 1000 kg/m³. It rises in a tube of radius 0.50 mm with contact angle zero. Question: Find the capillary rise. Givens: - γ = 0.050 N/m - ρ = 1000 kg/m³ - r = 0.00050 m - cos θ = 1 Assumptions: g = 10 m/s²; narrow circular tube, complete wetting, static rise, large reservoir and negligible meniscus volume. Choices (LaTeX): A. 0.010\ \mathrm m B. 0.040\ \mathrm m C. 20\ \mathrm m D. 0.020\ \mathrm m Ask for my approach first. Help me distinguish a physical misconception from an algebra error without revealing which choice is correct. Tutoring approach: Act as a patient physics tutor. Ask what I understand and what I have tried, then wait for my reply. Teach one step at a time; do not give the final answer or a complete solution immediately. Start with a physical picture. Define unfamiliar symbols and operators, explain signs and units, and state the model's assumptions. Give progressively stronger hints only when I need them. Ask me to predict a change before calculating it. When I finish, help me check dimensions and a limiting case, then ask one related transfer question. If information is missing or ambiguous, ask rather than inventing it. Distinguish exact results from approximations and acknowledge uncertainty.
Start with the smallest hint.
Work through it with me.
One decision at a time. Pause, predict, then unpack the algebra.
Balance upward surface-tension force around the rim against the weight of the liquid column.
Choose a physical relation
The vertical surface-tension force around the contact line supports the extra liquid column.
Isolate what is asked
Balance upward surface-tension force around the rim against the weight of the liquid column.
Why is this step valid?
With zero contact angle cosine is one; cancel one power of radius before substituting in metres.
Substitute and interpret
Rise is 0.020 m, or 2 cm; the tube radius must be converted from millimetres.
Substituting the height makes the upward rim force equal the column weight.
TRY THE IDEA AGAIN
If contact angle exceeds 90°, does the liquid still rise above reservoir level?
YOUR LEARNING NOTE
How does this idea feel now?
Confidence is a reflection, not proof of mastery.
Loading… · 0 answer checks
Loading your learning note…