00:01
So for this problem, we're mixing two jars of water that are at different temperatures, and we want to know what the final temperature would be.
00:09
So our first amount of water is 200 grams of water at 90 degrees celsius.
00:17
Our second group of water is 100 grams at 30 degrees celsius.
00:23
So let's just add our units here.
00:24
So our mass is in grams.
00:28
And then c here is our specific heat.
00:32
So the equation that we're using here is mc delta t equals mc delta t.
00:35
It comes from this equation here, which is q equals mc delta t.
00:39
So m is mass, which is in grams.
00:42
C is specific heat, which is a specific number or constant that is specific to a substance.
00:50
So water, for example, has a very specific heat.
00:54
And the unit for this will be joules per gram.
01:00
Degrees celsius.
01:03
And our temperature is obviously degrees celsius.
01:06
We'll just add that in.
01:08
So it's basically just filled this equation in for both of our values here that we have for each of our groups of water.
01:14
And then we're just going to solve for t.
01:17
So let's go ahead and do that.
01:18
So if we do 200 times 4 .2 over here, we will get 840...