Water Definition and 1000 Threads

Homework Statement This was a test question I had today but basically, initially the mass is at rest as the buoyant force opposes the force of gravity. Then we push it down X meters and let it go. This can be described by SHM. We are also given the density of water, a cross sectional area of...

Calculate the area of water, suspended at 500m, needed to produce 23TWh of energy I've done a calculation but the answer seems far too small If I needed to store the UK's supply of energy for three months i.e. 23TWh of energy in a reverse pump hydro storage at an elevation of 500m using P=mgh...

ok i want to make 1g/sec of hydrogen out of an unlimited supply of water, i know the electrolysis won't start below 1.48 volts, let suppose i am supplying 2 volts of DC current, i need to find out the total wattage for electrolysis, for this i need the amount of current required to produce 1...

Hello! I'm having trouble finding out how to calculate the force with which a river can push an object, well an propeller to be more exact. I would like to know what do I need to find about the river, like speed and cubic metres, and how do I use this information to calculate the force with...

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...

Hello, if I had salt water and put microscopic spheres with iron spikes in (a lot of them, say 1,000). Then if a high static charge was applied to the water (say 500,000 volts), what would happen? My intuition tells me that the electric field would concentrate on the tips of the spikes, making...

Hello Forum, I am reviewing water and its 3 phases (solid, liquid and gas). a) At the triple point, water can be in the three phases simultaneously. Does that mean that for a certain amount of water, say 30grams, we would find, approximately, 10 grams of liquid water, 10 grams of ice and 10...

If we say electron behaves as wave, does this mean if we were able to see an electron, we would see it moving up and down?

Greetings! I'm trying to evaporate water in some samples. I'm trying 3 methods. Baking samples with 100°C, normal air pressure, and normal RH. Put the samples in 0% RH, 23°C, and normal air pressure. Put the samples in container of -15 psi air pressure, 23°C, and normal RH. The total amounts...

What will happen? And why?

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

Picture a piping system made up of threaded steel pipes. It is to hold regular water at 7-10 bars. When testing the system for leaks, air is used due to a frost issue and the consequences of a larger leak with water. But what holds water doesn't hold air, and so it slowly leaks out. The question...

It has always been my impression than spectral type M stars were notorious for being flare stars. As a result of their small radius and relatively low effective surface temperature, the Habitable Zone has to be relatively close to the surface of the star and small in size. As a result, it...

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...

Homework Statement "In part 2 of the lab you will be firing a water balloon over a tall fence, aiming to hit a target." The fence is 3 meters high. You may fire the balloon from anywhere behind the fence, up to 4 meters away from it: the target will be 20 meters away. Find the angle to shoot...

Homework Statement [/B] A nail is heated in a bunsen burner flame and is about to be dropped into a beaker of water at room temperature. a) Which of the two substances (nail or water) would you expect to initially have: i) the highest internal energy ii) the highest average kinetic...

Homework Statement Find the net force of water on the dam The dam has a width of w and the water is at a depth of d. So my question is, would you have to integrate ρgwd with respect to d? because the pressure is constantly changing every value of d. Homework Equations ρgwd ρ is the density of...

The accepted explanation for the existence of water as a liquid involves hydrogen bonding. Why is this phenomenon absent in the case of hydrogen sulphide?

Assume the water flows from the faucet sufficiently slow.

Can anyone tell me about the operational problems involved with filtration in water treatment plant?

Homework Statement Hi, I have an assignment to determine the specific heat capacity of water using a calorimeter, voltmeter and ammeter, where we connected the calorimeter to a 10V power pack and measured the temp of the water and the readings on the voltmeter and ammeter every minute. I ended...

I am not a mechanical engineer; but I have physics background. I want to lift about 250 watts of heat from a metal block. At the same time I have to maintain its temperature at 30 deg Cel. For this I want to use water-air heat exchanger (HE). Heat exchanger will have inlet & outlet pipes. Hot...

Hello, I'd like to know which of these 3 example I sketched would have a steadier and higher air humidity at measuring point, assuming same conditions (except those illustrated as different, like porous media thickness and measuring point), water level and air turbulence within larger container...

Given a lot of room, talking hundreds of feet of piping, and potentially hundreds of square meters for equipment, how fast can you drop an input ranging from 50-100C down to 5-10C? It can also be partially underground (shallow). In this case, I could use the waste heat, especially if it's in a...

Homework Statement When, using a eudiometer in a lab to collect gas over water, if you have to switch eudiometers is the final volume of water displaced equal to the water displaced in the first tube + the water displaced in the second, and would the pressure be calculated through the total...

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.

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...

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...

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...

Does anyone here have any analytical experience with dissolved gas, particularly CO2? When CO2 is dissolved in water there can be several reactions: What I would ideally like to do is dissolve CO2 into water and then by some means of analysis, see how much of each species there is in the...

Here is a problem that showed up on my exam that I couldn't find any variation online. A stick of length L is depth D in the water. The stick is parallel to the surface of the water, and the viewer (in air) is looking down in the water right over the middle of the stick. What is the apparent...

Homework Statement HELP! L-shaped tank problem! figure: http://www.webassign.net/hrw/hrw7_14-33.gif The L-shaped tank shown below is filled with water and is open at the top. (a) If d = 7.0 m, what is the force on face A due to the water? (b) What is the force on face B due to the water...

Homework Statement Evaluate the experiment below, identifying energy loss and errors, and access their effect on the efficiency? The experiment was 'Determining the efficiency of energy conversion of boiling water in an electric kettle'. The method/system - 1. Weigh accurately 1000g of water...

Homework Statement A tube of length '##L##' is filled completely with an incompressible liquid of mass '##M##' and closed at both of the ends. The tube is then rotated in a horizontal plane about one of it's ends with a uniform angular velocity '##\omega##'. Then which of the following...

Homework Statement We are given two identical thermophores. It is known that one of them can boil a liter of water in t = 600 s. How much time would it take to boil one liter of water if we used two of these thermophores, connected a) in a series circuit b) in a parallel circuit Voltage: 230 V...

Water can dissolve O2 and CO2, both of which are non-polar...According to my understanding, water can only dissolve molecules which have polarity in their structure( like salt or sugar)...Oxygen gas is non-polar due to same atoms...I am not sure about CO2 but I think it is non-polar due to equal...

Homework Statement A 1x106 kg piece of ice is placed into a lake. How much heat is taken from the lake to raise the temperature of the ice from 0 °C to 1x10-20 °C? How much volume does the lake increase by? Latent heat for water is 334x103 J/kg Homework Equations Found in my textbook, cice =...

Hello bright minds, I have a practical problem for which I need help solving, and I'm sure someone could help. I am wanting to place a pick up (sort of a backwards facing venturi type structure) under my kayak to fill up and supply a box with fresh water for my live baits. I would like to know...

How much energy is required to inflate a volume of 102,102cm3 with ambient air at 5cm below the surface of a water tank. The surface of the water tank is 8 meters above sea level. The object to inflate is a rubber cylinder which has a diameter of 50cm and 52cm in length with 0 resistance from...

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.

Homework Statement Some underwater fish use a jet to move forward. The body expands with water and contracts, expelling water and thus propelling forward. For these purposes, assume that a submerged fish experiences a friction drag proportional to its surface area ##A_s## and proportional to...

Seems like the US is having a raw deal, have you checked your water is safe to drink? https://www.sciencedaily.com/videos/0233de5148b63e6e2bd95b0fcb0daca8.htm

Homework Statement Use Bernoulli’s equation to calculate how fast the water emerges from the open tap (at position 2) in the figure(a). You may assume that the water at position 1 moves negligibly slowly (b) The tap is rotated to create a fountain as shown in (b) Calculate the maximum height h...

Ice melting in a box has the water coming off it at a temp just above freezing until all the ice is gone. Are all phase change materials pretty much the same, with their immediate containment container exterior staying pretty much just above their phase change temp until all the PCM inside has...

Homework Statement How many degrees of freedom does water vapor have Homework Equations Translational up to 3 rotational up to 3 Vibration up to 6 The Attempt at a Solution Well I said water vapor had 3 translational. It can move along the x, y, or z axis I said it had 2 rotational (the...

Homework Statement A domestic kettle is marked 250 V, 2.3 kW and the manufacturer claims that it will heat a pint of water to boiling point in 94 s. (a) Test this claim by calculation and state any simplifying assumptions you make. (b) If the kettle is left switched on after it boils, how long...

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...

I understand that pure water that's being aerated will only take up just so much dissolved oxygen (DO) and that that depends on the temperature of the water. I see ranges of 14 ppm at close to freezing and around 6 ppm at 50 C as normal maximums. I understand, too, that you can temporarily...

if the person sitting in the boat throws a pebble to the swimming pool. Pebble was initially contained inside the boat and of course it has higher density than water.

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 belowhttps://www.physicsforums.com/attachments/105576