Read about water | 174 Discussions | Page 1

  1. Johnnyallen

    B Water pressure affects air pressure

    In the movie The Abyss an oil rig crew works and lives at the bottom of the ocean in a deep sea structure. There is a compartment where there is an opening in the floor allowing the crew to lower a submersible craft without going through any kind of air locks etc. We all should know from high...
  2. N

    I Pressure in a sealed vessel

    I have a sealed vessel, it is 200 ml, it contains 25 ml of water which is then saturated with CO2 (bubbled through at 0.3 l/min unitil pH drops, ~ 1 h) at rt. The vessel is then heated to 130 °C. I wish to calculate the final pressure of the system. Thus far I have calculated the volume of CO2...
  3. manareus

    Instrument name for water sampling and analysis

    Hello, thank you for your attention in my thread. I'm the head of Youth Science Club on one of the many High School in Indonesia, I got many members and I want to guide them for doing water sampling and analysis. In the history of my high school, no one is able to do water sampling and...
  4. Zachrz

    Safe Endothermic reactions for skin

    Hi, Its my first time here in PF, I was wondering what could be a fast endothermic reaction(with water) that does not burn the skin/ cause severe allergic reactions when/after touching or in contact with the reaction. (With high rate of cooling and hopefully no bubbles or gas forming). E.g to be...
  5. L

    A Superionic and metallic states of water and the Anomaly of Water Black ice I knew the Black Ice Theories since around 1990 -- Demontis, P., LeSar, R. & Klein, M. L. New high-pressure phases of ice. Phys. Rev. Lett. 60...
  6. Elder1994

    Find the electric dipole moment for a water molecule

    The equation that we saw in class is for a continuous charge distribution, I think that for this exercise I need to treat the system as a discrete charge distribution but I'm not sure. Also, I don't know how I can calculate the intensity of the electric field needed to move this charge.
  7. F

    B Sailboats providing their own wind

    I happened to be watching this cartoon and this one scene seriously bothered me... This... just feels like it wouldn't be a workable solution. Am I wrong? I can't say I perfectly understand how fans or propellers work, but I would imagine that by pushing air or water in one direction, equal...
  8. WhiteWolf98

    Clausius-Clapeyron equation to estimate sublimation pressure of water

    Before this question, the questions were about the Clapeyron equation, and how to estimate ##\Delta s##. I'm completely put off by this question however, and don't know where to start. I've found that the triple point of water is at ##0.01°C##, and there is indeed data in the table for...
  9. I

    B Underwater thrust formula?

    I'm trying to determine the force needed for one object to displace another object underwater. Specifically, Object A strikes Object B hard enough to jettison it from the seafloor up to sea level/land, let's say the Pacific coastline. I have a timeframe in mind, density & mass of the two...
  10. somasimple

    Hydration shell software?

    Hi, Is there Hydration/solvation shell software? I mean softwares able to show ions/molecules and surrounding water molecules forming hydrations shell?
  11. person123

    MATLAB API For Wave Flume Data Analysis

    (As a quick note, 'wave flume' should be taken rather generally. I basically just mean the sort of experiments involved in the flow of water which may use instruments such as pressure gauges, load cells, wave gauges, and ADVs. I know that they're not always done in a flume per say -- the...
  12. J

    A Negative pressure

    Hi everyone! I am working with the theoretical solid phase diagram of water and I would like to know what negative pressure means. Thank you in advance!
  13. C

    I Comparing Water and Ice Melting for fighting fires

    Good morning, I'm wondering on this question for a while. Imagine we have a fire progressing in a corridor 30 meters wide at a known velocity. What kind of barrier (of the following) can be most successful in minimizing or even erasing this fire and why: a water-soaked area, or a zone covered...
  14. D

    Misc. Hydrostatics problem in a water vessel

    I am trying to design a water vessel system that maintains it's water level as it is consumed. In item 1. It's a simple water barometer, where the height of water in the column can be supported by atmospheric pressure until 10.34. In item 2. There are two columns that are open to atmosphere...
  15. doglover9754

    B Why does water not follow the law of motion?

    So I was in the bus going to school. I sat in the back not directly underneath the emergency exit but more like behind it. Anyways, since it’s been raining consistently, the emergency exits sometimes leak. So I’m sitting down and my jacket sleeve gets wet with a drop from the emergency exit. I...
  16. C

    A Flow of Water into a Bowl with Holes

    I'm facing a problem with that rhyming title up there. The design is thus: a downward-facing, vertical pipe with known constant flow and diameter has water flowing out of it, into a short (15cm-91cm) free fall. At the end of that fall is a bowl of indeterminate depth made of steel with holes...
  17. jappy190

    Calculating charge density of particular ligands

    Hi everyone, this is my first thread! I am currently undergoing a personal investigation that is based on one of the factors which effect the splitting of d orbitals in central metal ion by the charge density of ligands (in a complex ion). However, recently I got stumped by trying to...
  18. R

    I Oil-Water-Salt - What's the force at work here?

    Hi, This is something I observed in the kitchen when I was cooking something. I had put some water in a vessel, to which, I added couple of spoons of oil. The oil formed large droplets on water surface. I then sprinkled normal table salt crystals on to the water surface and they sank to the...
  19. D

    Determining the flow rate for a cooling system

    MODERATOR'S NOTE: HOMEWORK INCORRECTLY POSTED TO CLASSICAL FORUM, SO NO TEMPLATE I need help with the following question: Please have a look at the question and my attempt at the solution. Alternative cooling systems are considered for a large computing centre requiring 1 MW of cooling...
  20. I

    Ideal fluid hitting a wall

    Hi, I`m seeking for help in the following problem. A flat vertical board is travelling in water which is to be considered as ideal. One of its ends is in water, the other one is outside the water. Its velocity is v with respect to its normal. What is the velocity of the water stream directed...
  21. L

    Calculating the wavelength of a surface wave after impact

    Homework Statement There's a bucket, filled about halfway with water. The water itself is completely still. A perfect sphere with mass m and volume v are given. The depth of the water, and the radius of the bucket (which may be considered perfectly cylindrical) are both given. In short, you...
  22. M

    Can we extract energy out of a capacitor in the ocean?

    Hello, sorry about my english it's not my mother tongue. I hope this is the right section to place this. 1. Homework Statement A cylindrical capacitor is placed in the sea so that when a wave comes (the water goes up), the water becomes the capacitors dielectric, when the wave has passed (the...
  23. A

    I Clear formula for water penetration by wave frequency

    I want a clear formula for clear water (and salty water) penetration by giving only the radio wave frequency . I searched the web , the formulas on the web are so complicated . Are there any simple formula available for that ?
  24. G

    I Rippled surface on lake ends abruptly

    Hi. I've made these pictures on Reichenau Island in Lake Constance, Germany. I was suprized about that clear line between the calm area close to the shore and the more rippled surface further out. The wind was weak, but directed from water to land. From a pier I could see that the ground drops...
  25. S

    Best anode materials for water-based hydrogen generator?

    I want also to build electrolysis based hydrogen generator or and water oxygenator/aerator. It's simple electrolysis device but requires special electrodes that are corrosion resistant or at least safe for human consumption. I seen that hydrogen bottles use platinum titanium electrodes. Platinum...
  26. Z

    I Carbon dioxide in liquid and gaseous phases with liquid water

    What are the differences between carbon dioxide solubility (miscibility, reaction) in liquid water when in gaseous (<38 bar) and liquid (>38 bar) phase? The temperature in my experiments is usually between 0 and 5°C. The stirring speed is around 500 rpm. Is the solubility given apart from...
  27. D

    B What is water impact velocity formula?

    Hello Everyone, I am brand new to this forum and I am currently doing "student research project task" where I need to conduct my own experiment basically. I am currently struggling to find a formula for an impact velocity. I hope there is someone in this forums that could help me. What I...
  28. J

    Water sometimes drips from the exhaust of a running car...

    Homework Statement You may have noticed that water sometimes drips from the exhaust of a car as it is running. Is this evidence that there is at least a small amount of water originally present in the gasoline? Homework Equations not sure if there is one. The Attempt at a Solution I'm not...
  29. Boltzman Oscillation

    I How does a the vertical force of gravity end in horizontal motion?

    When a stream of water falls perfectly vertical, some water hitting the surface will disperse horizontally. What is the force that causes this? References would be awesome!