Specific Definition and 1000 Threads

Homework Statement 3.00 kg of molten lead is allowed to cool until is has solidified. It is found that the temperature of the lead falls from 605 K to 600 K in 10 s, remains constant at 600K for 300 s, and then falls to 595 K in a further 8.4 s. Assuming that the loss of heat energy remains...

For an isochoric process, dV = 0 therefore dW=0 So from 1st of Thermodynamics, dQ = dU + 0 or, n*Cp*dT = n*Cv*dT (Cp and Cv denote molar heat capacities of the gas at const pressure and volume resp.) therefore we get Cp = Cv .(how can this be possible once we know Cp - Cv = R ?)

Hello there, I am so confused about the term battery specific energy (in Wh/kg) and specific power (in W/kg) Actually, I know what it means by power and energy, of course P = E/t But looking at the text, which quotes like "Ni-Cd batteries have high specific energy (than Ld-acid) but...

how does specific heat of gases vary with temperature? is there an equation to describe it?

Homework Statement Determine the specific heat of a liquid USING a resistance heater. Exact problem - Design an experiment complete with instrumentation to determine the specific heats of a liquid using a resistance heater. Discuss how experiment will be conducted, what measurements need to...

Bate, Mueller, White: Fundamentals of Astrodynamics (Dover 1971), p. 29, equation 1.6-4 for the eccentricity of a satellite's orbit: e=\sqrt{1+\frac{2\mathcal{E}h^2}{\mu^2}} e \text{, eccentricity} \mathcal{E} \text{, specific mechanical energy} h \text{, magnitude of specific...

what are the Cp and Cv values of petrol and air?

Homework Statement 0.1kg of ice was added to a lemonade of mass 330g at an initial temperature of 28 degree celcius and it completely melted. Considering only the lemonade and ice cubes, calculate the final temperature of the lemonade. Given: specific latent heat of fusion of ice= 336000...

a 210 heater is places in 2 kg of water. What temperature rise is produced if the heater is switched on for 200 seconds? I need your help please.

I have list of numbers like 3100002 11200002 11200011 12010011 12010020 20110002 20110101 21001020 21001110 30000300 100300020 . . . . I need all possible combinations of specific size depending on some conditions. size of combination can vary from 3 to 25. I am doing it...

Homework Statement My book states that "The only way that we can show that the function f(x) = \sqrt {1 + x^{4}} has an anti-derivative is to take a definite integral, \int^{x}_{0} \sqrt {1 + t^{4}} dt This is a new function that cannot be expressed in terms of algebraic...

Homework Statement Find the equation of the form y = Cekt if it passes through (0, 4) and (5, 1/2) Homework Equations y = mx+b? The Attempt at a Solution When I see "find the equation", my instant reaction is to find the derivative of y = Cekt. Once I have the derivative (or the...

I'm trying to figure out how to build a breadboard instrument using either push buttons or logic switches as they keys that will play each note. The issue that i am having is that I don't think finding all of the perfect resistor and capacitor combinations for each note is a good idea. So, i...

Homework Statement (a) Steam coming from a geyser at 100°C expands as it rises into the air. Since this expansion is rapid over the first small time interval we can assume that this occurs with no heat loss to the surrounding air in the region of the vent. What happens to the temperature...

Hello I do not remember the layout for posting and it is not posted because I'm on my mobile phone but I need help finding volume of hot water given the volume and temp of cold water and the temp of hot water. I need help finding specific heat given mass and temp and I...

If specific orbital energy for an elliptical orbit is -\frac{\mu}{2a} , shouldn't that mean that the further from the Earth an orbit is the lower its specific orbital energy? The Wikipedia page on specific orbital energy (admittedly not the best source) indicates the opposite, and if it were...

Hi, I am trying to shade two portions of the polygon defined by the dotted line in this code. The Mesh and MeshFunction cmds seem to allot global shading only. What is the best tool to shade, say half of the aforementioned polygon? Function[{LtMarg, BotMarg, RtMarg, HVal, DVal, rVal}...

Homework Statement Must the specific volume of a substance change when it undergoes a change in pressure? Is this true for all substances? The Attempt at a Solution obviously this is true in most cases but my question is: are incompressible liquids an exception? When a liquid is attempted to...

Homework Statement Calculate the energy need to change 9 g of ice at -20 degrees Celsius to steam at 110 degrees Celsius. (C for ice=2.06 J/g, C for water=4.18 J/g, C for steam=2.02 J/g, Hf of ice=334 J/g, Hv of water=2260 J/g) Homework Equations Q=hv / Q=mHf / Q=mc(delta)t The...

IS it possible? say if the specific heat is 800 and the composition is made up of 2 materials one which has specific heat of 850 and the other of 750

Homework Statement i just don't really get the one step subgroup test, which is very important, and something i should understand. can someone walk me through in general how to use the test? maybe give me a simple example? thanks. Homework Equations The Attempt at a Solution

Hi everyone, I'm not a computer scientist by any stretch, so I really apologise if this is a stupid question. This is my situation: I'm trying to help out one of my colleagues who has written a highly numerically intensive program which consumes RAM. He now has a large number of...

Homework Statement I heated 50mL of water in a Dewar and measured the temp. change with time. however, this only gives me the heat capacity of the system. I again measured but with 100mL of water, in an attempt to correct for the unknown heat capacity of everything but the water. However...

Homework Statement In order to find the specific heat capacity of an unknown material, a 50g piece is heated to 80 degrees Celsius and fully immersed in a well insulatyed calorimeter filled with 100g of water at 10 degrees Celsius raising the temperature of the water by 5 degrees, the heat...

Homework Statement A .4lb piece of Hg at 210 F is placed in .3lb of water that has a temperature of 70.0f. The water is in .1lb brass calorimeter. What is the final temperature of the mixture? Homework Equations Q=MC(deltaT) The Attempt at a Solution The part that I'm...

Q. Thermal energy is supplied to a melting solid at a constant rate of 2000 W. Calculate the mass of the solid changed to liquid in 2.0 minutes. Assume that the specific latent heat of fusion of the solid is 95 000 J kg-1 and that heat exchange with the surroundings may be neglected. I was...

Homework Statement A block of wood with a specific gravity of .6 with a volume of 100 cm^3 is made to just float in H2O by hollowing out some of the wood and replacing it with a substance of specific gravity of 6.5. How many grams of wood were replaced. Homework Equations Not totally...

Homework Statement The following data is obtained: Weight of ice cube added 20 g Weight of copper calorimeter 80.5 g Weight of water in calorimeter 105 g Initial temp of ice cube -18 deg C Initial temp of water 23 deg C Final temp of water 6 deg C Specific Heat Capacity copper 385 J...

can you please state some liquid which is a good heat conductor (which have low specific heat capacity)

Homework Statement A stoppered bottle, weights 38.215 g when empty , weights 45.362 g when filled with water. When filled with unknown liquid the bottole and unknown weighs 44.221 g. Calculate the liquid's specific gravity : Homework Equations D = m / v s.g.. = density of...

Homework Statement To summarize, I am given 6 objects and their corresponding specific heat capacity and thermal conductivity values. All objects have the same mass. The question is asking me to rank the objects based on temperature if they are put in a hot oven until they reach thermal...

[b]1. ammonia at 20 c with a quality of 50% and a total mass of 2 kg is in a rigid tank with an outlet valve at the bottom. how much liquid mass can be removed through the valve assuming that the temperature stays constant? and from so table in the text saturated press.= 857.5kps (@20 c)...

Homework Statement Finding the specific heat capacity of an unknown metal. A cylinder was placed into boiling water, originally at 24.2 C. The heat transferred from the metal, and the water then was 29.5 C. Original Temperature-24.2 C Temperature after the metal has been placed into the...

Homework Statement alright so i have to find the density of a clay unit. I am given a specific weight of the clay as 120 b/ft^3, the gravity constant as 32.17 ft/s^2. i need to find the density of the clay, i have no problem arranging the equation below to solve for density but I am not used...

I have been able to read through up to here (middle of pg. 60). The instructions given are not clear: (I arranged the text so as to be easier to read on the page here.) "Next, let's apply rules (2.4.8), (2.4.9) Eq. (2.4.8): U(\Lambda,a)J^{\rho\sigma}U^{-1}(\Lambda,a) =...

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...

Homework Statement A mass of 200 grams of copper, whose specific heat is 0.095, is heated to 100° C, and placed in 100 grams of alcohol at 8° C contained in a copper calorimeter, whose mass is 25 grams, and the temperature rises 28.5°C. Find the specific heat of the alcohol. Homework...

Homework Statement If you pour 0.50 kg of molten lead at 328°C into 2.5 liters of water at 20°C, what will be the final temperatures of the water and the lead? The specific heat of (solid) lead has an average value of 3.4 X 10-2 kcal/kg • °C over the relevant temperature range.Homework...

Homework Statement A fire hose held near the ground shoots water at a speed of 6.5 m/s. At what angle(s) should the nozzle point in order that the water land 2.0m away. Why are there two different angles? Homework Equations v=v0 +at v^2=v0^2 +2ad d=V0t+1/2at^2 The Attempt at a...

The specific heat at constant volume of an unknown solid is measured at high temperature to be 319.5Jkg-1K-1. Estimate its molecular weight. Cv=3R Attempt. I used the above equation to get a mass of the solid to be 0.0128kg but I have no idea of what to do next!

"What is the specific heat capacity of a 50-gram piece of 100 degree C metal that will change 400 grams of 20 degrees C water to 22 degrees C? Could someone please explain to me how to do this problem? I have to figure it out on my own because my teacher is no help at all. Thanks in advance.

Homework Statement Hello, I'm having some trouble with a lab report. I am supposed to find the specific heat of five metals but I don't know exactly how to use the equation correctly. for instance I have copper at 70.2g, the delta T at 1.8 degrees Celsius, specific heat of copper is 385...

For an ideal monatomic gas, the molar specific heat at constant volume, Cv=3/2R, where R is the gas constant. The heat capacity at constant volume of a gas is measured to be 43.58kJK-1. How many kg-moles of the gas are present? Iv tried looking in the lecture notes and in the...

Given the molar mass of Fe and the specific heat of Sn, what is the specific heat of Fe and the molar mass of Sn in approximate values?

Homework Statement Consider a linear array of N similar atoms, the separation between nearest neighbours being a. Discuss the specific heat of the system on the basis of the Debye approximation and show that at low temperatures, the specific heat would be expected to be proportional to T...

Homework Statement a crown that is supposed to be pure gold has a mass of 850g. Its apparent mass when immersed in water is 798g. (a) what is the volume of the crown? (b)is it pure gold?If not, what is the percentage by volume of gold in the crown assuming that the crown is an alloy of lead and...

I am digging back thorugh thermodynamics textbooks, and am seeing insulation values etc. but none on how to solve for time required to heat a material. Here is the specific problem. I am trying to fgure out how long its takes to cool (or alternately heat) a concrete slab. The slab is 8...

I was wondering is there any way to quantify how much "power" a given selection has on the final outcome of a voting. More specifically, say you have a sample 330,000 people and you need to pick one. However, before you get to make a choice a pre-selection is applied and the sample is narrowed...

Homework Statement The specific heat of substance X is 200 J/g*C, how much heat is required to change the temperature of 2.0 kilograms of substance X from 40 degrees Celsius to 55 degrees Celsius? Homework Equations Q=(m)(c)(change T) The Attempt at a Solution 55 C-40 C= 15 C...

There are often posts on the soapmaking forums about using one's own soap before it is cured. Curing time for soaps made with oils that solidify at room temperature is four to six weeks. For 100% Castille (olive oil) or similar, the curing time is six months or longer. Of course, we all...