Water Definition and 1000 Threads

Homework Statement The weight of a glass full of water is being measured using balance. a. An object is fully immersed so that some of water spilled out. How is the reading compared to before the object is immersed? b. If the experiment is repeated and now the object immersed has same volume...

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...

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...

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...

if I have a pool that is 20x20 surface area and I put a 200 gallon block of ice it, the water level will go up by X amount. when it melts how much will the water level change?

When one boils a pot of water on the stove, the water starts to boil into steam at 212 degrees Fahrenheit. The stove provides the heat both to make the water 212 degrees, and the stove provides the heat to change the state of the liquid water to vapor. However, we all know that water (or any...

Hi, The speed of light is given c=1/√(ε0μ0) where ε0 is permittivity of vacuum and μ0 is vacuum permeability. The permittivity and permeability of a material is given as ε=εrε0 and μ=μr)μ0 respectively where ε is absolute permittivity of the material and εr is relative permittivity of the...

Good day all ! I have a confusion regarding the use of the formula dU=CdT for computing internal energy for liquid or solid like for instance in this exercice We have an isothermal process so I thought that dU=0 so according to the first law of thermodynamics dQ=-dW (we want to calulate the...

Hello (This image is taken from Physics textbook grade 10. The book has been published in Pakistan) My question is: why do see the lion inverted in water in this image? I think it is due to the process of continuous reflection. But I am not sure. I need your help. Thanks.

Homework Statement Find the initial velocity of the boost phase (when water is coming out). Here is everything I know - Mass of rocket with no water is 0.13kg, mass of rocket with water is 1.1kg. The total length of the rocket is 0.48m. The time to the maximum point is 3.46 seconds, and total...

I am trying to understand how fluids form particular shapes when put on a solid. In the two figures,what are we taking as a system for the forces? How the resultant of the forces influences the shape of the different fluids?

Astronomy has been a fascination of mine for many years. As they discuss water on asteroids, I'm curious to see what everyone thinks. Do you feel this gives merit to the panspermia theory?

So I'm going to try to keep this as brief as possible, but I have a somewhat advanced physics question that my nuclear background hasn't prepared me for and I need an argument settled at work. Say you have a 30 ft deep pool and you need to protect the contents, which comprise the bottom ~10 ft...

Homework Statement An insulated piston-cylinder device contains 5 L of saturated liquid water at a constant pressure of 150 kPa. An electric resistance heater inside the cylinder is now turned on, and 2200 kJ of energy is transferred to the steam. Determine the entropy change of the water...

Hi, I`m seeking for help in the following problem. A flat vertical board is traveling 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 up...

Hi there! I'm teaching about rain shadows to 6th graders, and I've reached a barrier in my content knowledge. For the water cycle to work, warm, wet air near Earth's surface has to rise. In general, warm air is less dense than cold. However, due to air pressure, air near Earth's surface is...

I've moved to a "new" house - built about 350-400 years ago. Firewood in a stove kind of works for heating a few rooms, but not the full house. So far it seems like the grid power tends to die about twice a month. Temperatures is expected to reach -25C (-13F) for the coldest couple of weeks...

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...

Hello all, I've been thinking about this while I fill up my water cup or when I fill up a bucket from a hose. In the attached images are the two scenarios I present. My question is, which scenario would be faster (meaning in which scenario does the bucket or cup become full in the shortest...

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...

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 ?

Hi all, I am new to this forum and seeking help with a project that I am working on at the condominium complex where I live in Thailand during the winter months. We currently have 3 ponds with water spouts in each pond. At this time the water nozzles spray (bubble up) to about 12-14 inches. My...

Homework Statement So given a ball, radius r, mass m ,an a known height y from the surface the ball is dropped from, how would you calculate the depth the ball goes to in water (including the water it displaces), with the density of the ball less than the density of water. Ignore surface...

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...

I have an old under the sink H2O water filtration system. Its main components are 2 cylinder type filters, one 2.5 gal. storage tank, one passive mechanical "switch" plus a birds nest of plastic tubing with zero leaks anywhere. The output (dispenser) is your standard gooseneck type with a...

Homework Statement How to calculate the specific work done. Homework Equations Water vapor initially at 10 bar and 400 °C is contained within a piston-cylinder assembly. The water is cooled at constant volume until its temperature is 150 °C. The water is then condensed isothermally to saturated...

Homework Statement 10 kg water temperature 293 K change to ice ( 263 K) at constant pressure. Calculate the entropy change of system Answer is ##-13.8×10^3 J/°C## Homework Equations ##c_p = 4180 J/kg-K## (water) ##c_p = 2090 J/kg-K## (ice) ##l_{water→ice} = 3.34×10^5 J/Kg## ##ΔS = \int...

I found a simulation tool on wolfram alpha where the pressure of a constant volume is calculated. The pressure is affected by the heating of a mixture of water and air inside the container. There is an explanation to how the pressure is calculated which seems pretty straight forward. But there...

Hello I have a problem when I dissolves NaCl in deionized water. I have a pH probe in my deionized water (lets say 1 L). Then I add 40 g of NaCl, imidiately the pH-value rises to about 9.0 (i'm logging hte pH value as a function of time). Then slowly the pH-value lowers, and after 11 hours ...

Homework Statement Calculate the amount of heat emitted when 12.4 g of water freezes to solid air. Homework Equations heat of fusion = 6.02 KJ 1 mol H2O = 18.02 g H2O The Attempt at a Solution 12.4 g H2O x 1 mol H2O/ 18.02 g H2O x (-6.02 KJ) / 1 mol H2O = - 4.14 kJ I am unsure whether the...

I would like to simulate a simplified version of this phenomenon: where I will assume that the viscosity is zero and the liquid can therefore swirl around "laminarly" forever according to some velocity profile that I specify. How can I calculate the shape of the surface, at least in this...

I found that water flowing from a tap is casting a shadow, somewhat like this: If you see through the water flowing from the tap, you can see that the pink colour of the wash basin is visible almost clearly. What is the cause of the flowing water casting a shadow? Is it because the...

Homework Statement The question is : "In a water purification process, one-nth of the impurity is removed in the first stage. In each succeeding stage, the amount of impurity removed is one-nth of that removed in the preceding stage. Show that if n = 2, the water can be made as pure as you...

At work, we have a cylindrical tank that holds water. The tank is 5 feet round and about 6 feet long putting the highest part of the tank at about 6 feet off the ground. The tank holds 1000 gallons of water. There is a valve on the bottom that I am needing to test and I can’t seem to find a...

Homework Statement A hose of inside diameter ##1.5cm## can reach a distance of ##1.5m##. A nozzle is inserted in the hose and water can now reach ##24m##. What is the inside diameter of the nozzle? The height is the same in both cases. Homework Equations Use continuity equation...

I'm seemingly having problems of having too much evaporation of urea in the preparation of a gel. The gel is formed by drying the components in a water mixture, and it takes hours to dry at 70 ºC and dries much faster at 100 ºC (also produces a gel with better consistency), but at 100ºC it seems...

Homework Statement A hinged water storage is shown below. Its top side is denoted as C, the narrow side as B and the long side as A. Assume water density is 1000 kg/m3 and gravity is 9.81 m/s2 Side A is hinged at the bottom edge and secured using a clasp at its top edge. Dimensions are: L =...

Hi, Can anyone give me a source from which I can obtain the radioactivity level in the coolant water circulating in the primary circuit? Thanks in advance.

Hello, apologies for the crude drawing. I was wondering if it is possible to have a centrifugal pump that pulls in water and pumps it out down like in the drawn picture? I know usually its to displace water up. I always see centrifugal pumps with discharge oriented up like in the photo. If it...

Is the maximum attainable vacuum from a water aspirator directly proportional to the pressure being forced through the tube of the aspirator? Are there any factors other than water temperature that will affect the vacuum performance of an aspirator? My idea goes like this, I've got an...

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...

I am currently working on heating a feed with a stagnant water jacket cylinder avoiding water flow by dipping the electrical immersion heater directly at the side of the cylinder jacket. With this scenario, I would like to know what equation should I use to determine the total heat requirements...

When water converts to steam while boiling a vapour dome can be formed, what is the degree of freedom inside this vapour dome and on the saturated points?

Hello again Physics Forums! I have a question about fluid dynamics. Perhaps someone here can help me out. I am trying to understand how a plume of water moving at some speed carries momentum within a body of water. For instance the ‘exhaust’ from a submarine propeller. I am having a hard time...

When light enters an ocean, the photons scatter elastic with water molecules yet the presence of opaque particles causes the depth to be limited. Is this scattering Rayleigh scattering? (like the scattering in our atmosphere) https://en.wikipedia.org/wiki/Rayleigh_scattering

Homework Statement A pyramid weighing 4000 lb has a base 6ft square and an altitude of 4ft. The base covers an opening in the floor of a tank in which there is water 4 ft deep. Underneath the floor of the tank and on the water surface there is air at atmospheric pressure. What vertical force is...

If I have a laboratory water bath (circulated for homogeneity in temp) that I will monitor over a period of time (probably 2 scenarios, an hour at most, and then at least 24 hours or longer), how do I quantify the effect of atmospheric pressure in our test lab. What I will do is use an...

Here’s my experiment: I have a wine glass half full of water. I tap the edge with a metallic object to make a ringing sound. I recently bought a nice microphone and some acoustic software (Spectrum Analyzer Pro Live) and I’m trying to analyze the resulting sound to determine the resonance...

What I am confused about is why do bubbles of air in water move up. I understand why solids and liquids would move up in water if they are less dense. I get the idea that the deeper you go in water the more pressure there is because of the more water weighing down on the water and so there would...

So I'm planning to build an above ground concrete fish pond. The size of the inside of the pond will be (L)2000mm x (W)500mm x (D)500mm. What I want to know before I go any further is will the poured concrete walls hold the pressure of the water inside. So if I know the pressure of water I'll...