Question

A calorimeter of heat capacity 25 J K−1 contains 140 g of a liquid; an immersion heater is used to provide thermal energy at a rate of 40 W for a total time of 4.0 min. The temperature of the liquid increases by 15.8 C. Calculate the specific heat capacity of the liquid. State an assumption made in reaching this result. I calculated and found the answer successfully but I have a problem at stating the assumption part. Can anybody help? I can also show the calculations if you like.

Answer 1

Okay, what was the principle that you used?

Answer 2

this is my answer @Mashy

Answer 3

Okay, but why did you use
Q of system = Q of calorimeter + Q of liquid?

Answer 4

because they need to be balanced in the end, in order for them to finish transfering heat

Answer 5

What principle is that?
What law of physics is that equation stating?

Answer 6

I don't know the exact name of the law @Mashy

Answer 7

First law of thermo
Energy conservation

Answer 8

oh so that's the statement I need to make, thank you so much @mashy

Answer 9

No no!

Answer 10

So, basically you used the fact that
Energy put into the system, via the heater, must have gone into heating up the calorimeter and the water. right?
But would that happen in reality?

Answer 11

nope there would be energy loss to the surroundings

Answer 12

Precisely
So
What was your assumption?

Answer 13

that's the problem, I can't understand what I need to say exactly

Answer 14

You just said it

"would it happen in reality?"

your answer" Nope there would be energy loss to the surrounding"

So in your solution, you assumed that........ there would be no........ ???

Answer 15

oh okay now I get it, thank you

Answer 16

sure!