00:01
Well, the thermal expansion in three dimensions formula is given by delta v is equal to beta times v times delta t, right? well, since coffee is mostly made of hot water, we will assume that its volume coefficient of expansion is theta water.
00:22
So the thermal volume coefficient of expansion of water, beta, w for water.
00:30
That's equal to 210 times 10 to the power minus 6 per decrease centigrade, right? now, to calculate the change in volume of the coffee, we substitute the values of beta, v and delta t.
00:51
So change in volume of coffee, let's write on c for coffee, is equal to 210 times 10 to the power minus 6.
01:02
Multiply by 350 multiply by 45 minus 95 45 minus 95 so change in volume is equal to minus 3 .675 cubic centimeter well the thermal volume coefficient of expansion of glass beta g g for glass equals 27 multiplied by 10 to the power minus 6 per degree centigrade.
01:43
Right.
01:46
Now let's find out change in volume of cup, right? so this equals 27 multiplied by 10 to the power minus 6 multiplied by 350.
02:03
Multiply by 45 minus 95, 45 minus 95.
02:10
So change in volume is equal to minus 0 .4725 cubic centimeter...