Specific Definition and 1000 Threads

Homework Statement A remote controlled toy car starts from rest and begins to accelerate in a straight line. The figure below represents "snapshots" of the car's position at equal 0.5 s time intervals. (Assume the positive direction is to the right. Indicate the direction with the sign of your...

< Mentor Note -- thread moved to HH from the technical engineering forums, so no HH Template is shown >[/color] Determine the electric field in point P with coordinates (2a,0), if there's thin rod charged with electric charge Q and it's laying on x coordinate with length from -a to a, and it...

Homework Statement mass, m, of water in kettle 1.5 kg power rating, P, of kettle 2.1 kW time interval, t, for heating 322 seconds starting temperature 4 °C = 277 K finishing temperature 100 °C = 373 K temperature change, ΔT 96 K electrical energy supplied, E = P × t...

why specific heats at constant pressure and volume are the same for an incompressible substance?

Hello! (Wave) I had a test today , it was given an AVL-tree and I had to find the height of the node with key $k$. That's what I have tried: Height(T,K){ if (T==NULL) return; pointer R; R=LookUp(T,K); int k=height(R); return k; } height(pointer R){ static j=0,l=0; if...

why is the molar specific heat of carbon(=6.1JMol-1K-1) so different from the predicted value of 3R≈25??

So, here's the set-up: A small stereo speaker is connected to a function generator. A concave lens, bearing a ball is place over the speaker. Now, the frequency is slowly increased in the function generator. My question is, Will the ball really bounce at a certain frequency? Because I am not...

Is there an attribute of spacetime that determines the curvature that will be caused by a specific mass thus resulting to the corresponding gravity? In other words: can there be "harder" or "softer" regions of spacetime where the same mass will bend spacetime less or more thus resulting to less...

Homework Statement Using coffee (specific heat capacity of 3.98 x 10^3 J/kg °C) calculate the increase in mass if you raised the temperature of a 353 g cup of coffee from 34° C to 97°C. Homework Equations Q=mcΔt The Attempt at a Solution I believe I just need to solve for m. However I have...

Homework Statement A card is drawn at random from an ordinary deck of 52 playing cards (which means there are 0 jokers). Give the sample space. Homework Equations A set that consists of all possible outcomes of a random experiment is called a sample space, and each possible outcome of the...

hello! is it possible to heat the core of an object or a specific point inside the object? or are there specific objects we can do that? obviously after heating a specific point inside the object, the rest of the object will conductively heat up too, but I wonder if there is a way to...

The low temperature heat capacity was experimentally shown to go as T^3 for low temeperatures (and as T for even lower temperatures for metals). This result came out of Debye's model after he modified Einstein's model, relaxing some of his assumptions. I have a few questions on Debye's model...

Hi Admin, please allow me to post this here: The General Formula for Specific Heat Capacity is: C(Total) = C(electron)+C(phonon) C(electron) = aT where a is the sommerfield constant. C(phonon) = bT^3 this time i don't know what is b (some constant) so my problem is, how can i determine b...

Homework Statement An audience of 2750 fills a concert hall of volume 35000 m3. If there were no ventilation, by how much would the temperature of the air rise over a period of 2.0 h due to the metabolism of the people (70 W/person)? Homework Equations Q= nCvΔT Cv= (3/2) R The Attempt at a...

Hi, I am working on an animated short movie about a mission to Venus. I have a few very specific questions to help me get an authentic look. Firstly, would an object in long term orbit around Venus (say a hundred thousand years or so) become coated in dust? If so, what colour? Secondly, what...

Homework Statement So I've been trying to find the specific heat capacity of the potato for a while and keep coming up with an outrageous number (over 700,000 J/kgC) Here's what I've found mass of potato = 0.15kg initial T of potato = 18 degrees C final T of potato = 83 degrees C (is this not...

Hi people not sure if this is feasible but this is the idea and like to hear your comments i wan 2 shine a specific color of light (could be colored LED, normal light,) to determine the wavelength n intensity of it, so i am thinking of using a photodiode and an opamp connected with a...

Homework Statement When 1.25 kg of a cold metal at a temperature of 263 K was immersed in 1.43 kg of water at a temperature of 365 K, the final temperature was 336 K. What is the specific heat capacity of the metal? Homework Equations Q=mc∆t -Q=Q[/B] The Attempt at a Solution The answer...

Homework Statement 1)[/B] A quantity of propane is contained in a piston-cylinder assembly. This working fluid undergoes a process starting from an initial state of 2.0 MPa and 60oC. At the end of the process the pressure of the propane is 1.0 MPa and the specific entropy is 0.089 kJ/kgK higher...

Homework Statement The mass flow rate through a steam turbine operating under steady conditions is 100 kg/s. Steam enters the turbine at 12 MPa and 400oC. A mixture of vapour and liquid water exits the turbine at 10 kPa. At the exit state 93% of the mass of the water is in vapour form. The...

Homework Statement So this is a problem that I am at a complete loss with. The question asked is, give an equation, using the quotient or power rule that derivative is equal to either sec(x) or cot(x). It doesn't matter which one, sec(x) or cot(x), just as long as the initial equation's...

I've been grappling with this problem for a long time, but I think someone on this forum may know about this. Minimizing the joint number of products of a system of boolean equations is well-studied, and has various software implementations. Those are the Quine-McCluskey and Espresso...

Homework Statement A 0.080kg copper container (specific heat: 387Jkg-1K-1) contains 0.30kg of water and 0.040kg of ice at 0°C. Steam at 100°C is passed into the water and its temperature stabilizes at 20.0°C. Find the mass of the water left in the container assuming the system is insulated...

Homework Statement The element rubidium consists of two isotopes, the stable 85Rb and radioactive 87Rb (abundance 27.83%). What is the specific activity of natural rubidium chloride? Use Ar85.47 gmol-1 for rubidium element, Ar 86.91 gmol-1 for 87Rb, and Mr 120.92 gmol-1 for RbCl. Homework...

The specific heat capacity of water is accepted to be roughly 4.18 J/gK. How would the specific heat value of a given water sample be effected when sediments and other forms of particulation, such as iron oxide from rust, are present? Would the mixture have a higher specific heat capacity value...

Hey. I am writing my master thesis, and I really need to find the temperature dependent heat capacity and expansion coffient for Cobalt. I have tried searching the internet, whitout luck. Please, can anybody help me. It is really important!

Homework Statement A solid copper cylinder, 50 mm long and of 10 mm radius, is suspended in a vacuum calorimeter. Wound on the cylinder is a length of fine copper wire which is used as heater and resistance thermometer. Initially the resistance of the heater is 100.2 Ω. A current of 100 mA is...

$$x=c_1 cos(t)+c_2sin(t)$$ is a family of solution to $$x''+x=0$$. Given $$x(\frac{\pi}{6})=\frac{1}{2}$$ and $$x'(\frac{\pi}{6})=0$$ find a solution to the second order IVP consisting of this differential equation and the given intial conditions. The answer key has...

How do I know which one of these two spheres have more specific heat capacity?

Homework Statement A nonlinear spring has a temperature dependent force law, F = -\frac{K}{T}(L-L_o)^3 At a temperature T = T_o and length L = L_o the specific heat at a constant length is C_L = C_o. What is the specific heat at T = T_o when the spring is stretched to length 2L_o...

Homework Statement Prove that √2 is irrational as follows. Assume for a contradiction that there exist integers a, b with b nonzero such that (a/b)2=2. 1. Show that we may assume a, b>0. 2. Observe that if such an expression exists, then there must be one in which b is as small as...

If I introduce a gas into closed vacuum system at a known rate let's say 10 SCCM there will be a subsequent pressure rise over time. Is that pressure rise gas species dependent. If I evacuate the system and introduce a different gas at 10 SCCM should I see the same rate of pressure rise? Im...

Homework Statement A pot on a stove burner contains 10kg of water and an unknown mass of ice at equilibrium at 0degC at time = 0min. During the first 50mins, the mixture remains at 0degC. From 50 to 60mins the temperature increases to 2degC. What is the initial mass of ice? Ignore the heat...

Homework Statement Find the mass of water that vaporizes when 3.39 kg of mercury at 243 °C is added to 0.476 kg of water at 90.0 ° Homework Equations q=mcT, q=mL The Attempt at a Solution When vaporising T=100degC. Heat lost by mercury = heat gained by water. 3.39kg x 139J/kg/C x...

Homework Statement A spin-1/2 system in the state \left|ψ\right\rangle = \left|0.5, z\right\rangle of the S_{z} spin operator has eigenvalue s = +\hbar/2. Find the expectation values of the S_{z} and S_{x} operators. Homework Equations \left\langle S_{x,z}\right\rangle = \left\langle ψ...

When doing an experiment to find the specific latent heat of fusion of liquid nitrogen, you find that 100 kJ of heat must be removed to freeze 3.8kg of nitrogen at its freezing point. What value will you get for the specific latent heat of fusion of nitrogen? Power=100kj M=3.8kg I don't...

I am currently autodidacting the basics of astrophysics, and I of course came across the term specific intensity. The book explicates that it is defined as the differential of intensity per frequency element. But is there a better explanation so that I could lean closer towards a visualization...

Hello everyone. I am a college graduate perusing independent research of my own. I'm trying to figure out how to calculate how fast a specific gas (hydrogen) will rise from an initial velocity of 0 in room air and temperature. Basically, I'm trying to figure out how fast hydrogen would be...

Homework Statement Here is the circuit: http://gyazo.com/1e11d9208da0aa29d10b72128844ad40 What is the Electric Potential at Point A? Battery 1: 6.76 V Battery 2: 11.8 V Resistance 1: 100Ω Resistance 2: 217Ω Resistance 3: 312Ω Homework Equations Kirchhoff's Rules V=IR The...

[/ATTACH][/ATTACH]I need some help designing my electromagnet because I am a bit lost with it I need to work out the gauge of the wire to be used, the resistance of the wire needs to match the battery's internal resistance for max power transfer I need to work out the most amount of turns...

I was wondering how I would go about working out the energy required to cut a material (e.g. stone or steel) if given a volume, and all the necessary values pertaining to that specific material? For example, how would I work out the amount of energy required to cut a steel block of dimensions...

A bottle has a mass of 33.00 g when empty and 97.55 g when filled with water. When filled with a mystery fluid the mass is 84.02 g. What is the specific gravity of the mystery fluid? Hopefully helpful equations: p = m/v (p = density, m = mass, v = volume) SG = 1000p Attempt: I'm...

Please help me qualitatively in the following points : 1) If in a system(consider a cylinder) fixed with a piston , if the piston is moved suddenly then how can a process be adiabatic. 2) I understood that the process would be irreversible but, if the process is adiabatic then is the relation...

Hello all, I realize this isn't exactly the correct place to post this, but I can't start a thread in the mathematics learning forum, I'm not sure if I am supposed to be able to or not. I realized that I threw away one of my instructors math books on Fourier Theory I was borrowing over the...

I'm trying to find specific reaction cross section 18O(p,n)18F in proton + O-18 TENDL (ENDF format). # p + 18O : (p,n) Total # Q-value =-2.51902E+00 # E-threshold= 3.64964E+00 # # energies = 45 # E xs 1.000E+00 0.00000E+00...

When two substances have the same temperature, the particles have the same average kinetic energy, right? So why is it that some substances take more energy to increase the temperature one degree even if the increase in average kinetic energy is the same? I'm referring to specific heat...

Homework Statement the answer is c) but i can't figure why ! is the more heat capacity substance lose and gain energy faster than the other one so it take more energy to get it's temperature raised by the same amount because it lose most of it very fast during the heating process ?

Homework Statement Download the mat file Gettysburg.mat. View in a new window and load it in the workspace using the command clear; load Gettysburg; This loads a 1-by-1452 char array GA that is the Gettysburg Address in English. Display the first 100 or so characters for yourself to see this...

I have been conducting a lab to find the force of a spring by calculating the oscillatory motion of the period. Each time i added a mass, i gained a higher spring constant, but on the 250g i ended up losing spring constant. I was wondering if anyone know why, or if i have done something wrong...

I have been looking for specific heat capacities of certain materials such as steel but i can never find a solid answer, so i figured i would test it myself, how would one test specific heat capacities?