# Physics

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You decide to take a nice hot bath but discover that your thoughtless roommate has used up most of the hot water. You fill up the tub with 270 kg of 30.0°C water and attempt to warm it further by pouring in 5.00 kg of boiling water from the stove.
(a) Calculate the final temperature of the bath water.
(b) Calculate the net change in entropy of the system (bath water + boiling water), assuming no heat exchange with the air or the tub itself.

• Physics -

sum of heats gained is zero.
heat in original water added + heat in boiling water gained is zero.

270c(Tf-30)+5c(100-Tf)=0
solve for Tf

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