1. X

    B How does water escape the pot?

    I was cleaning up the kitchen, and there was a large pot that had been filled with water to soak in the sink. A rectangular nylon pot scrubber was hanging over the side of the pot, about 2/3 in the pot and 1/3 hanging out. As I ran the tap, the pot filled up and overflowed, but even after the...
  2. Ryaners

    Chemistry Calculating the number of water molecules in trans. metal complex

    Homework Statement [/B] I had an inorganic lab this week which involved making VO(acac)2 from VOSO4⋅xH2O. In order to calculate the percentage yield, I need to work out x, that is, the number of water molecules coordinated with the vanadyl sulfate n-hydrate before the reaction. I'm stuck...
  3. J

    Is a hydronium (H3O+) less clear than a water pool (H2O)?

    Not that I know of any hydronium pools, I was just wondering if there would be a difference in clarity or not (as in, harder to observe the bottom)
  4. S

    Acoustics and Fluid Flow - COMSOL 4.2

    Hello everyone, First of all I am new here~ Second, I would like to "prove" on COMSOL that soundwaves (sound vibration) can alter/reshape the fluid flow Can someone tell me the physics i should use as well as all the other parameters to make it work? if someone is more experience can they...
  5. O

    Power drawn by a water pump to project water through nozzle

    Homework Statement [/B] This is problem 10.27 in the Exercises for the Feynman Lectures on Physics, or Problem C-2 in Chapter 10 of Leighton and Vogt's Exercises in Introductory Physics. Homework Equations Using ##v_f^2 = v_i^2 + 2 a S## for the water in the vertical direction, we can find...
  6. A

    Need an explanation -- Consider pure water separated from...

    Consider pure water separated from an aqueous starch solution by a semipermeable membrane, which allows water to pass freely but not starch. After some time has elapsed, the concentration of starch solution a. will have increased b. will have decreased c. will not have changed d. might have...
  7. Tomimo

    Making bubbles and trying to use Trompe

    Hi, I am trying to create a device that would "simply" make a bubble under the water. What I am aiming for is production of small bubble but continuously and under the water. When I say continuously, it doeant have to be for extended periods of time, could be just for ~2 hours but the longer...
  8. Adrianus

    What heat capacity is needed to evaporate water in oil

    Homework Statement In an industrial fryer is f.e. 400 kW. Heating capacity installed. The fryer may contain as much as 1.450 ltr of oil. I can fry 2.000 kg of chicken nuggets per hour in that. These products loose 7% of moisture/water in this process. That water can only escape from oil in gas...
  9. B

    I Why sound produced by rapids varies in pitch based on height

    The other day I was at a river listening to some rapids. The sound produced by the rapids appeared to vary in pitch depending on how high up I was (squatting down to the ground and standing up produced about a fifth in the variation of the pitch); and I can't think why it should be? Many Thanks
  10. G

    I Water model for electric circuits: Pipe diameter?

    Hi. There's this nice water circuit model for electric circuits where pressure corresponds to electric potential and the (mass or volume) flow rate to electric current. In the water model, we can vary the pipe diameter along the circuit. Since water is practically incompressible, the flow rate...
  11. cookiemonster13

    Oxygen formation in Earth water

    I always wondered why they say water and photons created the first microbes which later evolved and produced oxygen which filled our oceans and atmosphere. So how could have water existed without oxygen? I tried to look up and came up with different explanations, but it doesn't make sense.
  12. supak111

    B Energy release from 75c drop in water temp, 1L?

    Hey everyone can anyone tell me how much energy is released (joules) if you take 1 liter of water at 100C and drop it down to 25C (room temp, reg pressure)? Is it significant amount? Better even how much energy is released (approximately) for every 1c drop in temp? Is the release in energy...
  13. J

    B Rate of sinking objects

    Hi All, I have a problem (with 3 separate instances) to which I believe I have the answers, but would like check with those more knowledgeable than myself. They revolve around 3 blocks sinking through water and which falls quicker. I am ignoring friction. Instance 1: All blocks are exactly the...
  14. C

    Blobbing - energy loss

    Homework Statement Blobbing is one of the extreme attractions in aquaparks. A person is lying on a big raft positioned on the surface of water and filled with low-pressured air. Another person jumps down from a given height onto the opposite end of that raft, throwing the lying person in the...
  15. F

    I Will my special siphon work please?

    Please look at this drawing of my idea, and tell me if you think it would work. The compressed air chamber on the left keeps this system un-balanced, and water is continually forced up the tube, and into the right hand chamber.
  16. CivilSigma

    Derivative in mass flow rate equation - Hydrology

    Hello, I am working with the mass flow rate equation which is: $$\frac{d \dot{m}}{dt}=\dot{m}_{in}-\dot{m}_{out}$$ To determine the change of the height of water in a reservoir. Assuming m_in = 10 and m_out = sqrt(20h), then : $$\frac{d (\rho \cdot Q) }{dt}=\rho \cdot Q_{in} - \rho\cdot...
  17. allister109

    B Does water pressure decrease in zero gravity?

    me and my friend were talking on facebook and we couldn't think of an answer to the question, would water pressure decrease in zero G, you can see how far along we got before getting stuck in the picture below
  18. euphorik

    Help me move a floating bridge 90 degrees w/o getting wet!

    Hello! I was hoping someone here could help me solve a real world problem. So my university pool has something called a bulkhead, which is basically a bridge that floats above the water so that people can walk across the shorter dimension of the rectangular pool (50 meters long, 25 yards wide)...
  19. Samwoodford1996

    I Water speed

    If you was to pour the same about of water though a thin funnel say 1 inch and through a big funnel say 5 inch which of the funnels will the water reach a higher speed ??
  20. AndresPB

    I Help with a Reference Level of Radon in Water

    Guys, I'm keep searching for a WHO standard of Radon of Water in Bq/m3 but I can't find one. Can anyone help me find some references of maximun contamination level of Radon in Water? It may be EPA, or something else too. Thanks a lot
  21. D

    I Do the Relative Permittivity and Refractive Index of Water Match Up?

    Many textbooks and online sources give the relative permittivity of water as about 80 and the refractive index as 1.33. If you use the definition of refractive index to find the speed of light in water, you will find v = c/n ~ 2.56e8 m/s. However, if you use the equation to find the speed of...
  22. E

    I Fun question: Can this fish swim?

    Imagine a fish in a tank that is completely filled with water and closed on all sides. Can this fish swim? Since water is extermely difficult to compress, when the fish moves its fin to propel itself forward, the water can't move anywhere, so the fish should not be able to move right? Then I...
  23. A

    Does the height of the water column on top of this pump matter?

    We are using the following pump to measure the strain on a special tube. http://www.instechlabs.com/Support/manuals/HABP.pdf This special tube is connected on each side to another tube that is connected to one of the two connectors on the pump. (The two connectors of the pump were put parallel...
  24. S

    Calculating flow rate through turbine

    Hi guys, First post on this forum. Greetings from the Netherlands :) I am currently in the process of designing a turbine used in locks in several canals. The turbine is powered when the lock chamber is being emptyed during the lockage. The goal is to calculate the water level in the lock...
  25. P

    B Is rainwater harmful for us?

    I've heard people say that if you come back from the rain and you're soaking wet (because of the rain water), you should take a bath to prevent any kind of illness. However, how can it be that rainwater can cause you harm, but the water in your home cannot? Or maybe, how does your home water...
  26. J

    Oil & water problem

    How does a ball floating 50% in water move when a large amount of oil is added, and why? MY Solution: I think that the ball rises because when a large amount of oil is added, the oil sinks to the bottom causing the water to be pushed up, increasing the buoyant force which causes the ball to...
  27. Tardis Traveller

    Ideal gas expansion

    Homework Statement A bubble comes from the bottom of the tank of water to the surface and triples in its volume. If the temperature of the tank of water doesnt deppend on the depth what is the depth of the tank that the bubble was at? Homework Equations ##PV=nRT## The Attempt at a Solution...
  28. Liam A

    I How to create a natural vacuum

    i work at a cavern attraction and one of the parts in the speech we say is that a section of the cavern was once filled with a naturally occurring vacuum until it was punctured and destroyed. we explain in the speech that the vacuum was created when a river packed in that area with mud and clay...
  29. S

    Setting Pressure on Relief valves on Water Cooled Panels

    Gentlemen, I work in the steel industry, specifically in the melt shop department which operates electric arc furnaces. My question is that those electric arc furnaces have water cooled panels around the furnace, and I am trying to install relief valves on the panels. the molten metal and slag...
  30. M

    How many kg of ice must be dropped to make Tf= 22.7C?

    Homework Statement An insulated beaker with neglible mass contains .3kg of water at a temp of 78.6 C. How many kg of ice at -19.6 C must be dropped into the water to make Tf= 22.7C? Specific heat for water= 4190 J/kgK specific heat for ice= 2100 J/kgK heat of fusion for water= 334kJ/kg...