00:01
We are looking at the expansion of a glass rod inside of a laser with a temperature change of 65 .0 degrees celsius.
00:07
So first we want to look at how the length changes of the rod.
00:12
So delta l is equal to the average linear expansion coefficient alpha times the initial length times delta t.
00:22
This one's easy, just plug in some numbers here.
00:25
9 .0 times 10, the negative 6, inverse degrees of celsius.
00:31
Initial length is 30 centimeters, but this is also going to be equal to 0 .3.
00:38
I'm just going to write meters, so that's clear.
00:41
And the change of temperature was just 65 .0 degrees celsius.
00:47
And you should find that the change of length of the rod is equal to 1 .76 times 10, to negative 4 meters, which is the same thing as 0 .176 millimeters.
01:04
To put that in perspective.
01:11
Okay.
01:12
So for part b, we're going to look at how the diameter changes d...