1
00:00:06,280 --> 00:00:08,870
YEN-JIE LEE: I decided
to include a lot of demos

2
00:00:08,870 --> 00:00:11,110
during my lectures.

3
00:00:11,110 --> 00:00:15,730
That is because I
believe to learn physics,

4
00:00:15,730 --> 00:00:20,650
you have to know how to convert
everything into mathematics.

5
00:00:20,650 --> 00:00:23,620
You want to work
on the mathematics

6
00:00:23,620 --> 00:00:26,290
and to make predictions,
and finally, you

7
00:00:26,290 --> 00:00:31,240
want to compare the predictions
to experimental data.

8
00:00:31,240 --> 00:00:34,090
Demonstrations are
particularly useful because I

9
00:00:34,090 --> 00:00:37,480
would like to show
that the mathematics we

10
00:00:37,480 --> 00:00:41,590
covered during the
classroom actually

11
00:00:41,590 --> 00:00:43,570
have a lot of consequence.

12
00:00:43,570 --> 00:00:46,900
It's actually really
to do with what

13
00:00:46,900 --> 00:00:51,390
nature does to all the physical
systems we are interested.

14
00:00:51,390 --> 00:00:54,140
So that's actually
why we first--

15
00:00:54,140 --> 00:00:56,090
usually the structure
is like this.

16
00:00:56,090 --> 00:00:59,110
We first introduce
the physical situation

17
00:00:59,110 --> 00:01:03,310
we are interested then
we use the concepts

18
00:01:03,310 --> 00:01:07,280
and the mathematics to
solve the physical system,

19
00:01:07,280 --> 00:01:11,110
and finally, the last part
is to enjoy what we have

20
00:01:11,110 --> 00:01:14,170
learned from this hard work.

21
00:01:14,170 --> 00:01:20,180
To compare our mathematical
solution to reality,

22
00:01:20,180 --> 00:01:21,910
which is actually the demo.

23
00:01:21,910 --> 00:01:28,180
So that is actually why
I introduce so many demos

24
00:01:28,180 --> 00:01:31,370
during the class, and
those, I do think,

25
00:01:31,370 --> 00:01:35,620
using those demos people
will remember more

26
00:01:35,620 --> 00:01:38,080
about the conclusion
we can actually

27
00:01:38,080 --> 00:01:41,080
get from the
mathematics instead of

28
00:01:41,080 --> 00:01:44,740
overwhelmed by a lot of
calculations during the class.

29
00:01:52,420 --> 00:01:57,550
There are so many interesting
demos which we covered.

30
00:01:57,550 --> 00:02:03,810
One of my favorite demos
is the Bell wave machine.

31
00:02:03,810 --> 00:02:07,670
First of all, it's really
a very beautiful demo.

32
00:02:07,670 --> 00:02:12,060
It is so beautiful to
see the sinusoidal wave.

33
00:02:12,060 --> 00:02:17,470
It can be produced from
this simple device.

34
00:02:17,470 --> 00:02:19,960
Secondly, you you can
actually manipulate them,

35
00:02:19,960 --> 00:02:22,540
you can connect
them to each other,

36
00:02:22,540 --> 00:02:25,420
and you can see waves
essentially bouncing

37
00:02:25,420 --> 00:02:29,170
between systems, and then
you can see the reflection

38
00:02:29,170 --> 00:02:30,700
of the traveling wave.

39
00:02:30,700 --> 00:02:34,020
It's so beautiful, and that's
actually my favorite demo

40
00:02:34,020 --> 00:02:34,990
during the class.

41
00:02:34,990 --> 00:02:38,740
I believe most of
the students are also

42
00:02:38,740 --> 00:02:42,180
interested in that
demo very, very much.