QuestionDetails: I received the following response and I am still unable tosolve

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QuestionDetails: I received the following response and I am still unable tosolve the problem. I am not sure which numbers touse. Also, what does the "c" stand for in the question? What does the "?" represent?    Hope you canlead me through this problem..... ResponseDetails: So, this problem wants you to essentially find the Power (J/s)leaving the wire, then convert Joules into temperature using Q =m*cp*T.

So, P= VI      You have voltage, you ahvecurrent. Plug and chug.

To get the change in temperature, you construct a solution which isa combination of both the water and the "r" (which is what i assumeis the wire).
So you're essentially creating a mass weighted average of the cp'sof the two fluids.
C total = m1*c1/(m1+m2) + m2*c2/(m1+m2)

Once you have your combined cp just say

Q per second = P
P /(mtotal* Ctotal)= T/second
To find the time for it to heat up 3 k, just say :
T/second *t =3 k
ResponseDetails: QuestionDetails: Temperature change time base problem. Suppose V = 30 V, I =0.2 A, mw = 46 gm, cw = 4.18J/gm?K, mr = 9 gm, and cr =3.7 J/gm?K. If the water is initially at room temperature, how longwill it take for the water to heat up 3 ?K? (Hint: dT/dt isapproximately equal to T / t.)

Explanation / Answer

C stand for the heat capacity. cw is of the water and cr is of thewire. I think the response is right, cant see any mistake. Can you be a little more specific about where are you stuck.

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