Temperature change Definition and 134 Threads

If I have a heating source that gives off constant single temperature heat which heats a mass of insulator, next to a mass of ice, next to a mass of cold water - how do I predict through calculation the temperature change over time of the water? I know the original temperatures, surface area...

Homework Statement trying to work out the answer for the temperature T from the equation... (1012)2=(2.8*1019)(1.04*1019)(T/300)3exp(-1.12/KT) Homework Equations the equation was derived from ni2=NcNv(T/300)3exp(-Eg/KT) The Attempt at a Solution Only simplified the equation to...

I'm very confused on about solving the following question using Matlab: A drink cools according to the difference equation: Tn=Tn-1-0.02(Tn-1-Ta) Where Tn is the temprature after n minutes. When you pour the drink it's 80 degrees. After you have poured it you leave it for 15 minutes in...

Homework Statement The following table shows the daily high tem- peratures for a week in May. Determine the change in temperature each day. Sun. 76◦ Mon. 72◦ Tues. 80◦ Wed. 75◦ Thurs. 75◦ Fri. 74◦ Sat. 78◦ Find the net change in temperature (the...

I'd like to ask how to calculate the rate at which the temperature changes, knowing the power input and the specific heat capacity of an object?

I'm interested in modelling the effect of a chamber of ideal gas at a high pressure passing through subsequent chambers of lower pressure gas - each subsequent chamber joined to the previous via a thin plate oriface. I'm looking at at an iterative solution (i don't do integrals) and i am...

Homework Statement In this investigation, you mix .5g of Mg(s) with 115mL HCl. You measure the temperature change which turns out to be 25.5 degrees C. The equation is as follows: Mg + 2HCL --> MgCl2 + H2 Use the specific heat of water (c=4.184) to find the heat of formation. What is the...

Homework Statement Two cars collide head on while each is traveling at 80 km/hr. Suppose all their kinetic energy is transformed into the thermal energy of the wrecks. What is the temperature increase of each car? (Assume each car's specific heat is that of iron) Homework Equations K =...

Hello to all, I'm reading one article about boiler. I have found one interesting fact about air preheater used in industrial boiler. It goes something like this "Approximately 1% of fuel is saved for each 40 F rise in combustion air temperature. Now, since I'm in Europe, I want to know how...

Homework Statement When you take a bath, how many kilograms of hot water (49°C) must you mix with cold water (12°C) so that the temperature of the bath is 36°C? The total mass of water (hot plus cold) is 191 kg. Ignore any heat flow between the water and its external surroundings. Temperature...

Can someone please help me on relating an induced magnetic field to entropy change, and ultimately a change in material temperature... Gadolinium (Gd) undergoes a change in entropy when a field of 7.5 Tesla is applied. This process is adiabatic and the initial temperature is 290K. Im...

Homework Statement A Pyrex container is filled to the very top with 40.0L of water. Both the container and the water are at a temperature of 90.0 degrees C. When the temperature has cooled to 20.0 degrees C how much additional water can be added to the container? Homework Equations...

Does anyone out there know if there are any published studies which have tested the tolerance changes in steel and aluminum machined components when they are manufactured in one (temperature) environment and moved to different (temperature) environment. Anything would help. Thanks,

I have been working on a series of questions dealing with gas expansion and temperature change for my PE exam. \frac{}{}

Homework Statement A 40mm diameter bar of aluminium is 2.5m long the bar is has its temperature raised from 20°c to 40°c. Determine the increase in length of the bar in mm. Take the Al = 24 × 10-6 °C-1 How much heat has been transferred into the bar if the SCH = 0.9kj/kg °C Homework...

Hello, I'm going to post a curious question. Today I found a case where I have no idea what to do. I'm working with the Thermal Conductivity and it's W/(m ºC) or W/(m K) then I don't know how to change from a way to the another one because kelvin and Celsius degrees are not...

Homework Statement What is the energy released as water changes temperature from 20C to -10C? Homework Equations mct+lfm+mct The Attempt at a Solution My physics exam is day after tomorrow, however, I have no clue about this question. I was away for a week during these lessons. Can...

1. How can I relate the time it takes for a box of volume 8000 L to change temperatures from Ti=300K to Tf=400K? Homework Equations The Attempt at a Solution

Bulb with volume of 5 liters is filled with nitrogen n = 3 molls. The bulb is set in space, the bulb cracks and the gas starts to expand. The nitrogen is considered as a real gas. Find the change in temperature. Joseph van der Waals' constant equals 0.137.

Hello, We have an installation in which we will be placing a 1/4" thick mirror which spans 7ft across and 5ft in height directly next to a "line of fire" (a gas pipe with holes which will have a flame approximately 6" in height). Our concern is that when the line of fire is turned on in...

k the question states On a pleasant fall day (temperature of 21.0 degree Celcius) a lump of clay (with mass of .855 kg) is thrown against the wall with a speed of 38.0 m/s. The clay deforms as it sticks to the wall, noiselessly. Assuming no heat escapes into the air, what will be the...

Homework Statement A person has 300 g of black coffee at temperature 350 K in a vacuum flask. 100 g of milk at 280 K are added to the coffee (the flask is immediately closed, so the loss of heat to the air is negligible). Assuming that the specific heat capacities of the coffee and milk are...

1. The problem statement: A 5.00 x 10^2 kg object is attached by a rope through a pulley to a paddle-wheel shaft that is placed in a well-insulated tank holding 25.0 kg of water. The object is allowed to fall, causing the paddle wheel to rotate, churining the water. If the object falls a...

A metal wire has a resistance of 8.70 ohms at a temperature of 20°C. If the same wire has a resistance of 11.20 ohms at 90°C, what is the resistance of the wire when its temperature is -20°C? R = Ro[1 + a(T-To)] Basically what I did was found a first by using the 2 given resistances and...

I have a question involving putting an ice cube in a thermos of coffee. I used c_{ice}m_{ice}(T_f-T_i) + c_{coffee}m_{coffee}(T_f-T_i)=0. Is this right? If so wouldn't the temperatures of the ice remain constant until it is all gone?It says that the ice is at 0'C.

Homework Statement Suppose a steel strut with cross-sectional area 7.00x10^-4 m2 and length 2.50 m is bolted between two rigid bulkheads in the engine room of a submarine. (a) Calculate the change in temperature of the strut if it absorbs an energy of 3.00x10^5 J. °C Homework Equations Q =...

How does our skin respond to changes in temperature?

1.) An iceberg's volume is 2*10^6 m^3. If the temperature of the iceberg is is 250 K and the density is .9998 g/cm^3, how much heat energy would be required to competely melt it? 2.) An object weighs 500 grams and has a specific heat of 2 Joules/g C. The object absorbs 40% of the output of...

I've been trying to solve this for about a week and I'm not sure where I'm going wrong. The problem is to figure out how much the temperature of the auditorium increases when its full of people. The room is 4350 cubic meters. The meeting lasts 30 minutes (1800 seconds) The specific heat...

An iron cylinder is heated to 100.degrees C in boiling water ant then transferred to 145.0 grams of water in a 70.0 gram copper calorimeter at 20.0 degrees C. If the final temperature is 25.2 degrees C find the mass of iron used. Would I use mL(Boiling water)+mcT(water)+mcT(coper...

A room has temp at +22 degrees C, and after 8 hours it has fallen to 15. What is the rooms "time constant" when the outdoor temp is -5 C? I have no idea what is beeing asked about here, could someone help me...?

In a chemical investigation I'm currently undertaking as part of a chemistry course I'm am studying I'm recording how the temperature changes in several reactions and using the rate of temperature change as a measure of the rate of reaction. I believe this is a valid way to do it as you...

A 4.2 g lead bullet moving at 260 m/s strikes a steel plate and stops. If all its kinetic energy is converted to thermal energy and none leaves the bullet, what is its temperature change? --- I don't even know what formula to use or how to start. I could get force, by multiplying the mass...

I'm having a problem solving two problems, wondering if someone can help me out... 1)Blood can carry excess energy from the interior to the surface of the body, where the energy is dispersed in a number of ways. While a person is exercising, 0.645 kg of blood flows to the surface of the body...