mainly parts a and b, i can't figure out, part C and D i have NO IDEA AT ALL...

but i need help with a and b at least..



with those equations..

am i missing any other equations, i really can't figure it out, can u guys help me out?

 

I'm no physicist--I'm a mathematician--but a) and b) should be pretty easy.

For a) compute the total heat in the system--temperature (K) * mass I believe--subtract the heat of fusion for converting the ice to water, then divide the remaining heat by the total mass to get the average temperature. This seems reasonable to me.
For b) compute the heat in the water at the start and at equilibrium and subtract the latter from the former. Again, this seems reasonable to me.

Hope you get a physicist for c) and d).

 

ok i got everything, thanks for ur help

it really helsp when i post this in 3 diff forums hahahhaa

cuz i get multiple explanations, it helps it soak into my head..

damn final 2mrrow!

 

Post the results, please.

 

technically u solve for part b first, but u dont know it.. so u just do Q = mc(deltaT)
for the water

Q=24510 cal

then u do Q = mL (L=latent heat)

and u get 34271

since the energy of the ice is higher than the water, the water does not have enough energy to melt the ice completely.. so the final temperature is "0".

and since u did q=mcdeltaT already, the answer for part b is 24510


part C,

Power = kA dT/dx
(watts)

also note that P = Q/time

since the question asks for half, u take "Q from part B, convert to joules, which is 102557, and divide by two, which is 51278.5 J

then u do P = Q/time
and calculate for time

and yea tahts part C

part D i was told wans't going to be on the test so i'm not worried hahahha... plus most ppl i asked were confused as hell

 

apply conservation of energy equation Ein - Eout + Egen = 0
in the problem, Egen should be 0 cuz there is no generated energy in the system... so basically u just have conduction of heat in the system through the chambers... and Econd = L/kA.... hope its helpful to you good luck!

 

D.) The process is irreversible because the two chambers are not in equilibrium with each other. Delta S = integral of (Cp/T) dT. The delta S for the water = Cp ln (273/301.5) = -.1 and the delta S for the ice = q/T = 34271/273 = 125.5

Delta S for the system = Delta S water + Delta S ice = 125.5 -.1 = 124.4 >0 which is what we expected for a spontaneous irreversible process.

-Insano

 

i already took my final today, so no more of this BS for me!!!!!

thanks for the help everyone