Thermal Coffee Cup
Thermal Coffee Cup questions and answers
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Q: Which has the greater amount of Thermal energy and iceberg or cup of coffee? Explain?
A: An iceberg.
Put very roughly, thermal energy is related to the amount of something you have multiplied by the temperature.
Let's assume your iceberg is at the freezing point of water - 0 degrees Celsius (which equals approximately 270 Kelvin, or degrees above absolute zero). Now your cup of coffee might be 75 degrees Celsius (approximately 350 Kelvin). 350 isn't a whole lot more than 270, but an iceberg is thousands of times larger than a cup of coffee. Even though the iceberg is at a lower temperature, it contains more thermal energy because it's not at absolute zero and it's much larger than the cup of coffee.
Q: Where can I get a quality thermal coffee mug?
I'm looking for a good quality travel cup that actually keeps coffee warm throughout the morning. I have had a few and all of them either end up leaking, cool off quickly or pour sloppily. Any suggestions on what to buy? Links would be appreciated. Thanks!!
A: I found the aladdin coffee mug at Target (sporting goods section), it has a real good heat retention level, you can close the lid, (it screws on tight) to keep it from leaking in case you are a klutz like me, has a little turntable on the lid to keep it closed, you slide it open to driink, and it is pretty well designed for driving and sipping. about 12 bucks is what i paid, and have had it for about 2 years, still keeps it hot.
Q: How do coffee shops charge you when you bring your own mug/cup?
A lot of people bring their own thermal cups to keep their drinks hot (and cut down on waste!). Does the store estimate how much your cup holds and charge you accordingly or what? But isn't it hard to estimate?
A: It's pretty easy to estimate how much coffee you are pouring when you do it every day...
Small mug=small coffee price
Large mug=large coffee price
Q: What coffee pot keeps your coffee the hottest? Drip, Percolator, or drip with thermal stainless steel carafe?
Alot of the stainless steel carafe coffee pots I checked out don't have a warmer underneath. Also the coffee pots that you put your coffee cup right underneath all have mixed reviews as to how long they work. I just want to find a decent coffee pot that keeps the coffee hot
A: I think an insulated carafe keeps it hottest without continuing to cook the coffee...I hate coffee that's been heated for hours.
Q: A 0.250-kg coffee cup at 20oC is filled with 0.250 kg of brewed coffee at 100oC.?
The cup and the coffee come to a thermal equilibrium at 80oC. If no heat is lost to the environment, what is the specific heat of the cup material? [Hint: Consider the coffee essentially to be water.]
A: Mc*Cc*(80-20) = Mw*Cw*(100-80)
Since the masses are equal, they cancel and I get (Assuming Cw = 1.0),
Cc = (100-80)/(80-20) = 20/60 = .333
Q: Okay, I give up. Why can't I get the sludge out of my coffee using my bodum thermal french press?
I'm using the coarsest grind I can buy at Starbucks. Do I need to buy a grinder for home and make it even coarser? I've read all the instructions and tips I can find. The plunger goes down (with some effort), but the coffee is invariably thick and not in a good way, to the point that there's a fine layer of silt in the bottom of the cup.
A: Grinding your coffe fresh is always best, as for your problem with sludge I'm afaid its part of the whole "French Press" thing.
If it bothers you just filter it through a coffee filter.
Q: Need help with thermal convection?
Ok I have a couple of problems I am having a hard time understanding and my text book isn't a lot of help.
Why do we put rugs down on stone floors during the winter?
Is it because stone has higher thermal conductivity than the rug?
What about if I wanted to cool a cup of coffee?
should I stir it, put it in a short, wide cup or put it in a tall narrow cup?
Same cup of coffee - would it be cooler in a white cup, black cup, black and white striped cup or pouring it between a white cup and a black cup?
A: You are correct that stone conducts better than the rug. Heat travels from hot to cold. In the case of the stone floor, your feet would conduct heat out to warm the floor. The rug does not conduct as well, and is acting as an insulator of heat.
For the coffeee, putting a cold spoon in it would cool it. Stirring it would cool it because tit would bring new areas to the top. A wide cup would cool faster because there is more area to have coffe evaporate, a cooling process, and to convect from.
Good radiators of heat are good conductors of heat. The white would reflect heat back. The black would radiate heat out better. Pouring it back and forth would cool it because of exposing the coffee to the cooling air, and more area for evaporation.
In several cases here your heat transfer was radiation or conduction, only convection from the top of the cup.
Q: How much energy does coffee transfer to piece of aluminum?
One way to cool a cup of coffee is to plunge an ice-cold piece of aluminum into it. Suppose a 20.0g piece of aluminum is stored in the refrigerator at 32 degrees F(0.0 degrees C) and then put into a cup of coffee. The cofee's temperature drops from 90.0 degrees C to 75.0 degrees C. How much energy (in kilojoules) did the coffee transfer to the piece of aluminum? Assume coffee and aluminum reach thermal equilibrium meaning same final temperature. The specific heat capacity of water and aluminum is 2.06 and 0.902 J g^-1degreesC^-1
A: Heat lost by coffee = heat gained by aluminium
Heat gained by Al = mc x delta T = 20g x 0.902 J/g-degC x (75 - 0)degC = 1353 J = 1.353kJ
Q: Thermodynamics: thermal energy?
A small electric immersion heater is used to heat 100g of water for a cup of instant coffee. The heater is labeled "200 watts", so it converts electrical energy to thermal energy that is transferred to the water at this rate. Calculate the time required to bring the water from 23 C to 100 C ignoring any thermal energy that transfers out of the cup.
The answer is 742 kJ. Can you show me the steps involved with solving this problem?
A: the answer you quote is an energy, not a time...let's follow this problem
200W means the heater adds 200Joules of energy to the water each second
the amount of energy needed to heat 100g of water from 23C to 100 C is given by:
Q=mc(delta T) where m is the mass of the water, c is the specific heat, and delta T is the change of temp
here, m=100 g
c=4.2 J/gram/deg C
delta T= 77
thus, Q=100 g x 4.2 J/g/C x 77C = 32.3 KJ
if the heater provides 200J/s, then the time needed to heat the water is
t=32.3kJ/200J/s = 161.7 s
Q: thermal physics HELP! please?
A small electric immersion heater is used to heat 71 g of water for a cup of instant coffee. The heater is labeled “99 watts” (it converts electrical energy to thermal energy at this rate). Calculate the time required to bring all this water from 21°C to 100°C, ignoring any heat losses. (The specific heat of water is 4186 J/kg·K.)
please help???
A: heat(in kcal) = w*t/4200
Where w is the wattage ( here 99 watts), t is the time (here t in seconds) and heat is the energy required to raise the temperature of the water from a certain point to the other higher point ( here from 21 degrees to 100 degrees).
First of all,
Heat energy required to raise the temperature of 71 grams of water from 21 degree to 100 degree is
(100-21)*71 = 79*71 = 5609 cal = 5.609 kcal
now putting 5.609 in the above relation
5.609 = 99*t / 4200
= 23557.8 = 99t
=23557.8/99 = t
= 237.957 = t
Therefore time is 237.957 seconds.
Converting it into minutes.
237.957/60
= 3.96595 minutes
Converting 0.96595 into seconds
0.96595*60=57.95
Therefore total time will be 3 minutes and 58 seconds (approx.)
Q: Physics: Specific Heat?
A 0.250-kg coffee cup at 20 degrees C is filled with 0.250 kg of boiling coffee. The cup and the coffee come to thermal equilibrium at 80 degrees C. If no heat is lost the environment, what is the specific heat of the cup material? [Hint: Consider the coffee essentially to be boiling water.]
A: In geneal
Q=mCp(T2-T1)
Q- heat energy
m mass of the substance
Cp - specific capacity of the substance
T2-T1 - difference in temperature
Q(water)=m(water) Cp(water)(T2-T1)
Q(water)=0.250 x 4.186 (100 -80)=
Q(water)=21J
Q(water)=Q(cup)=m(cup)) Cp(cup)(T1-T3)
Cp(cup)=m(cup)) (T1-T3)/Q(water)
Cp(cup)=0.250 ( 80 - 20)/21=
Cp(cup)=0.714 J/(g K)
Note that Cp's are always using degrees K, however since since we are using Centigrade scale thee difference between two temperature reading will be the same.
Q: How do you keep French Press coffee warm after brewing?
My boyfriend and I LOVE pressed coffee. I'm sure I don't need to explain to veteran coffee purists why it's so tasty. Anyway, he likes having more than one cup to drink (as do I), but our problem is that he takes FOREVER to finish a cup, and by the time he's done and ready for a refill, the coffee is cold. I've thought of buying a thermal carafe, but not sure if it is worth the investment. I've also re-heated in a microwave, but it tastes awful that way. Any tips or advice?
Also, this video shows another good way to brew coffee, but I don't know where to get that filter Alton Brown uses...any suggestions there?
A: Hi, Dani,
I use a tea cozy on my french press but my daughter and I drink our coffee. We don't nurse it along. May it would be wiser for you to make two smaller pots.
The Muse
Q: chemistry homework help?
Could someone please show me step by step how to do the following equation, I can't seem to figure it out.
A piece of titanium metal with a mass of 20.8 g is heated in boiling water at 99.5 degrees celecuis and then dropped into a coffee cup calorimeter containing 75.0 g of water at 21.7 degrees celcuis. When thermal equilbruim is reached the final temp is 24.3 degrees celcuis. Calculate the specific heat capacicty of Titanium?
A: qTi = mTicTi(Tf - T1)Ti
qH2O = mH2OcH2O(Tf- T1)H2O
qTi = -qH2O
mTi x cTi(Tf - T1)Ti = - mH2O x cH2O(Tf - T1)
solve for cTi
cTi = - 75.0gH2O x 4.184J/gK(24.3 - 21.7)/20.8gTi(24.3 - 99.5)
You will get a minus sign for the delta T of Ti, which will cancel with the minus sign in front of the right side of the equation.