Temperature and Thermal Energy of coffee cup

AI Thread Summary
The discussion revolves around calculating the heat absorbed by a glass coffee cup when it is placed in hot dishwater. The user expresses confusion about physics equations, specifically mentioning the heat transfer formula Q=mC∆T. They correctly identify the mass of the cup as 0.4 kg and use the specific heat capacity of water (4180 J/kg·K) to compute the heat absorbed. The final calculation results in Q = 100,320 J, indicating the amount of thermal energy transferred to the cup. The user acknowledges their earlier mistakes in unit conversion and calculation, highlighting the learning process.
mppaki
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Before I begin, Please note that for some reason I don't really grasp physics equations which is odd since I had a A in chemistry but physics just confuses me and also, I am taking this class to prepare me for college. My pencil broke and I didn't think we would have homework of the stuff we learned so quick, so I decided not to ask anyone for a pencil and just listened through the rest of the lecture but now I regret it.

1. A 4.00 x 10²-g glass coffee cup is at room temperature, 20.0°C. It is then plunged into hot dishwater, 80.0°C. If the temperature of the cup reaches that of the dishwater, how much heat does the cup absorb? Assume the mass of the dishwater is large enough so its temperature doesn't change appreciably.



Homework Equations


The only thing I can think of is Q=mC∆T, but I am pretty sure that is the wrong formula.


The Attempt at a Solution



m = 4.00 x 10²g = 4000 / 1000 = 4kg.
Ti = 20.0°C
Tf = 80.0°C
C = 4180

Q = (4)(4180)(80-20)
Q = 1,003,200 j/kg * K
 
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m = 4.00 x 10²g = 4000 / 1000 = 4kg.
Check this one.
 
oh, um the 1000 is because i needed to convert the grams to kilograms.
 
It should be 400/1000 kg
 
oh yes lol, I have a habit of entering in my calc the x10...

Q = (0.4)(4180)(80-20)
Q = 100,320 J/Kg * k
 
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