Specific Definition and 1000 Threads

Homework Statement Hi there, I am trying to complete a thermodynamics assignment. I am doing fine until I get to the following question. "Hx = Specific enthalpy at dryness fraction = hf + x . hfg" - I am not quite sure where Hf came from, I guess they want a value for Saturated liquid from...

[An object with mass 30 kg and specific gravity 3.6 is placed in a fluid whose specific gravity is 1.2. Neglecting viscosity, which of the following is true? A. The acceleration of the object is 1\3g and its apparent weight is 100N B. The acceleration of the object is 2\3g and its apparent...

I have this infuriating little problem I'm trying to solve: How many ways are there to produce 2 bucks out of any number of coins? So this means - how many ways to get 200 by adding 1, 2, 5, 10, 20, 50, 100. The best idea I could come up with so far in my research was counting multisets...

Hi, I know very little about maths. I'm struggling to get my head around a question I was asked today, and I was wondering whether someone could explain it to me. Question: If a very large group of kids took it in turns to roll a die again and again until it landed on '1', on average how...

was heated to 86.6 C and then placed in a calorimeter that contained 61.2 grams of water at 19.6 C The temp of the water rose to 21.3 , determine the specific heat of the alloy in J/gC " Technique: use the formula c= q/delta t what do you plug in for q ? you would have c = q/1.7 ? what do you...

50 grams of a substance absorbed 2.578 kj of energy as it changed from 25 degrees celcius to 89.7 What is the specific heat of the unknown substance in J/gC ? Is it correct to use : q = m c delta T q = specific heat m = mass c = ? delta T here is 64.7 The answer seems really big? Is it ...

I am doing a lab about specific heat. i have a cup of boiling water which i put 5 metals into, and a cup of warm water which sits at 22 degrees celcius. i am to record the difference in temperature as i am using the equation Q = mc (delta) T for part one, and then i am using the equation C = Q/m...

Homework Statement How can you calculate the specific heat capacity of an unknown metal? In my question the metal with a mass of 50g and a temperature of 200 degrees celsius was placed in 125 g of water with an initial temperature of 20 degrees celsius. After the simulation and the metal...

Hi, I have been using both ANSYS APDL and ANSYS Workbench (Mechanical) to run analysis on a structure. After loading the structure, in Mechanical i was able to scope my results for deformation and EQUIV stress to just the adhesive layer as this is what I am interested in. However, I can't...

Homework Statement This was a LAB assignment. I need to find the specific heat capacity of a given metal (Cu in this case) in water, I have the following observations. Mass of water: 249.14g = 0.24914 Kg Initial temperature of water: 18 C Initial temperature of metal: 100 C Specific heat...

Or maybe to ask the LOR-writer if they think I'm particularly exceptional on some trait I mention?

Special relativity Length Contraction and Time dilation question Homework Statement Planet X is 18 Light Years from earth, A spaceship moving towards the Earth at a speed of 0.82C (Measured from Planet X) fires a series of 1.2 cm long and 2.1 gram mass (as measured by the pilot) projectiles...

Ok this is a simple question that has made it difficult to figure out. For a visible wavelength of light from a laser source, the beam is visible due to Rayleigh scattering. If the photon is wavelike in classical and macro states then wouldn't that prohibit the coherent nature of a laser beam...

my understanding is that energy is wasted in a solar cells when light with more frequency than necessary to make an electron cross the band gap comes along and the excess energy is converted to heat. does this mean if you only shined blue light at a solar cell which had a perfect electron gap...

Homework Statement A block of weight sits on a plane inclined at an angle \theta as shown. (Intro 1 figure) The coefficient of kinetic friction between the plane and the block is \mu. What is the work done by the applied force of magnitude ? Express your answer in terms of some or all of...

Homework Statement What is the specific heat of seawater? Homework Equations I'm confused about what units are used, and what the specific heat of seawater is defined at? The Attempt at a Solution I found a website quoting, 'specific heat is about 3850 J/(kg C)'

I'm confused about what units are used, and what the specific heat of seawater is defined at? I found a website quoting, 'specific heat is about 3850 J/(kg C)' Is this correct, with these units?

Homework Statement The ice piece of 380 g was taken from the deep-freezer, temperature was -9,6 °C, and well insulated container to the being stone-cold ( 0 °C) water. Inside the Ice piece was small temperature detector. When temperature of the the ice piece had balanced 0 °C. part of the...

Hi, Working on a project, I am told to find the K,n value of a specific transistor (2n7000), given the spec. sheet. I know K,n can be found from the formula: I,d = K,n * (V,gs - V,tn)^2 I'm close, from the spec sheet, I can use a V,gs value and a corresponding I,d value, however not sure what...

Homework Statement \int dx/(x4 + 16) Homework Equations Hint: With a>0, x4 + a2 = (x2 + \sqrt{}2ax + a)(x2 - \sqrt{}2ax + a) The Attempt at a Solution I've plugged this into the equation, which leaves me with: \int dx/[(x2 + \sqrt{}2ax + a)(x2 - \sqrt{}2ax + a)] But now I...

Homework Statement A 5.00-g sample of aluminum pellets (specific heat capacity = 0.89 J/°C · g) and a 10.00-g sample of iron pellets (specific heat capacity = 0.45 J/°C · g) are heated to 100.0°C. The mixture of hot iron and aluminum is then dropped into 96.5 g of water at 23.5°C. Calculate...

Given a set of 2D coordinates (real numbers, involves positives and negatives), I could calculate the (weighted) barycenter by simply using the logic with plain numbers. For the barycenter calculations, I sum all the values with respect to x-axis and y-axis separately, and then divide with the...

Imagine there are 2 space-probes in space. Both of them start their engines in the same time. The first space-probe has a very low level of thrust but a very high specific impulse. The second space probe has a very high thrust but a very low specific impulse. Both of them have an equal amount...

We have the parameters,current =10^-3A,V=15kv,number of electrons=6.25 X 10^15,velocity=7.3 X 10^7,specific heat capacity of the liquid=2 X 10^3,c=3 X 10^8,h=6.63 X 10^-34,mass of electron = 9.11 X 10^-31. Now the question says,in an x-ray tube having those parameters,find the rate at which...

First of all, hello everyone :) . Second of all, I'm looking for magnets that are brick-like. They need to be pretty strong. Dimensions, ideally, would be 1" x 1" x 2.5 - 3". Can I get rare-earth magnets that do this? I'm not sure where else I can post this, so if it's in the wrong...

is there any specific name for a coffee cup handle in mathematics?

Homework Statement A student wants to melt a 200 gram block of ice that is at minus 10.0°C and turn it into liquid water at 15.0°C. The student plans to do this by heating copper pellets to 100.0°C and then dropping them onto the block of ice in a thermally insulated container. How many...

Homework Statement 1.0 g of water at 28 degree celcius is placed into a 200g aluminium can at 300 degree celcius. What is the temperature of the aluminium can after all the water vapourises? Given the specific heat capacity of aluminium, 900 J/kg/degree celcius and water, 4200 and specific...

Homework Statement This is a problem I made myself and it's really confusing me. You have 100mL of water and place it in a calorimeter of low specific heat capacity. You put another 100mL of water in another calorimeter of high specific heat capacity. Assume in both instances that the water is...

So, I can't really find this limit: \lim_{T \to \infty} \ 3Nk {(\epsilon/kT)}^2 \frac{e^{(\epsilon/kT)}}{{(e^{(\epsilon/kT)}-1)}^2} This is actually the formula for the specific heat of an Einstein solid, which is pretty easy to derive but I haven't been able to calculate the limit to show it...

Hi, I am trying to calculate the amount of heat required to raise the temperature of a rubber sphere by 20 degree's Celcius within 10 seconds. The rubber sphere will be heated via radiation in a closed system. I have calculated the specific heat capactity, by using the formula q =...

Homework Statement write down the Lagrange-Charpit eqs for \frac{ \partial u}{ \partial x} \frac{ \partial u}{ \partial y} - y \frac{ \partial u}{ \partial x} - x \frac{ \partial u}{ \partial y}= 0 and use them to show \frac{ d^2 p}{ d p^2} = P assuming that u = x^2 when y=0...

Imagine the skyscraper and the very long rod placed on its top that rotates from horizontal position to upwards. http://img109.imageshack.us/img109/4817/fhfn.png I would like to know how is it possible to calculate/ascertain the maximal length and minimal width of the rod made of some...

Homework Statement So basically our teacher gave us a bunch of materials and told us to conduct an experiment including the notes on change of heat we took earlier in the week. This is what my group conducted. We acquired 125 mL of water that started at 21 degrees celsius. We then heated...

Why is specific rotation not a colligative property? i just read that it depends on concentration(gm/litre) but i feel that it should depend on molarity considering the fact that rotation is due to changes in molecular structure...do i have a point or am i just being silly ...can someone help me?

I need to confirm something about combinations: 1. I need to find the combinations of 5 out of 35. <=> 35C5 = 324.632 combinations. 2. Now I want to try to "fit" these 324.632 combinations of five numbers into sets of 6 numbers. To do that, I first find how many combinations of five numbers...

1. A pressure vessel of volume 100 liters is filled with 1 kg of liquid water and 80 liters of steam with a specific volume of 0.02 m3/kg. Determine a. The density of the liquid water in SI fundamental units b. The mass of the steam in grams c. The density and the specific volume of the system...

1.the Schrodinger’s cat on test 2.wave - particle two-phase nature 3.entangled state 4.God does not play dice 5.the Bell inequality Please advice about the above statement should be how to write correctly?

So I don't get the concept of specific heat. I'm doing an ODE problem and I've never even looked at science, not even in high school. The book defines the specific heat of a substance as: The ratio of the quantity of heat required to raise the temperature of a unit of substance by one degree...

Homework Statement A piece of metal of weight 50 grams is heated to a temperature of 100°C and then introduced into a calorimeter containing water at 14°C, the maximum temperature reached being 20°C. If the weight of the calorimeter is 5 grams, the specific heat of the metal of which it is...

I just heard "Cherish" by the Association on the oldies station, and immediately flashed back to the Freshman welcome dance in HS. It was a VERY hot song, and it was the first song played at that sock-hop for the Freshman-Senior waltz. I got chosen by a friend's sister. Cute and chesty in her...

Dear Forum members, I have a bit confusion about the "Specific Heat at constant pressure". Normally it only varies with the temperature (As given by many book at their Appendixs). But these values are only given at 1 atm pressure and with a wide range of temperature. Most of the books...

mechanical (work) unit is J/kgK Heat unit is kcal/kgK what is this mechanical (work) unit, Heat unit ? I'm not able to understand it. please elaborate

In another forum that I frequent, I have been having a discussion where the state of quantum gravity research came up. Another poster claimed that one of the first thing that any gravity scientist checks for the theory is the theory's prediction for the precession of Mercury's perihelion. Now...

An ice-cube has a mass of 7.50 g. The ice-cube is at 0 °C. Heat from the surroundings reaches the ice-cube at an average rate of 1.25 J / s. How long does it take for all of the ice to melt? (specific latent heat of fusion of ice = 333 J / g) A 35.5 s B 55.5 s C 2000 s D 3120 s

The question involves testing the Specific Heat Capacity of an aluminum block, using the equation: Q = m x Specific Heat Capacity x Change in Temperature. Two experiments are performed using the same power of the heater and the same mass of the object and a very similar change in...

I constructing 3D shape of about 2 millimeters sized. Which kind of optical coating will give me 10 degrees of half view angle for reflected light in visual spectrum ? thanks Alex

Homework Statement A cylindrical disk has volume 8.97 x 10^-3 m^3 and mass 8.16 kg. The disk is floating on the surface on some water with its flat surfaces horizontal. The area of each flat surface is .640 m^2. What is the specific gravity of the disk? How far below the water level is its...

Hello. I am writing an encryption algorithm for a program and have decided to use a hill cipher. My problem is that for the hill cipher, I have to have matrices with very specific properties. How might I go about finding 3 matrices of size 4x4 such that all of the matrices are integer-only and...

Homework Statement The experiment was that we heated a beaker with water in it, and also a type of metal for around 5 minutes so that the metal becomes the same temperature as the water. We then dropped that heated metal into a stryofoam cup containing 189.10g of water in it. mass of...