Set-2
A Very Boring Lecture**
Some Tools for Later
** Sorry about that
Where Are We??
Read the rest of chapter 1
Read pages 288 - 294
Two Useful Topics
• Scientific Notation
• Converting Units
Don’t be offended if you already know this stuff.
Feel free to take a nap.
An Atom
~0.0000000002 Meters
9 zeros after the decimal point !!
~0.0000000002 Meters
Datsalottazeros!
Dersgoddabeabedderway
And there is!
Do you remember?
2  2 2  4
2
2  2 2 2  8
3
2  2  4  8  32  2  2  2  2  2  2
2
3
2
3
2

3
5
2 2  2
 2  32
5
The Sequence
•
•
•
•
•
•
20=1
21=2
22=4
23=8
24=16
25=32
• 1,2,4,8,16,32, …….
Interesting but would be better
if we only had one finger on
Each hand!
Counting in BINARY
Which is better for
counting?
5
1
This works for other
“bases”
1 2
6  6  6 6 6  6
1
2
 6  216
3
You use what you have …
• 5 fingers on each
hand.
• 2 hands
• Toes are inaccessible
• 2 X 5 = 10
• Lets look at “base” 10
“Base” 10
10  1
0
10  10
1
10  10 10  100
2
10  10 10 10  1000
3
Some of the numbers
10  1 _
0
10  10
1
10  10 10  100
2
10  10 10 10  1000
3
A real number
{
1
6,500,000 (6 million)
2
6
6.5 1000000  6.5 10
6 Zeros
Scientific Notation
What about decimals?
Example :
7
7
0.0007 
 4
10000 10
7
7 10  4
4



7

10
10 4 10 4 10  4
ONE
Better : 7.0  10  4
So..
7.0  7.0  10
0.7  7.0  10
0
1
0.07  7.0  10
2
0.007  7.0  10
3
0.0007  7.0  10
4 places after
The decimal
point
4
First non-zero
digit
Powers of 10 (meters)
What’s it all about??
Powers of 10
http://www.youtube.com/watch?v=41g
WUkVQ-9U
PowerPoint Version also available.
Does Scientific Notation
have any use in music??
The Path of Music
The Path
of Music
The Ear
“Loudness” increases with
The AMPLITUDE of the
Back and forth movement of the
eardrum.
More on Loudness
later in the semester
Last Topic in this Set
UNIT CONVERSION
• We need to convert days to seconds
• How many seconds are there in 2
days?
• What do we know?
1 day = 24 hours
1 hour = 60 minutes
1 minute = 60 seconds
UNITY
24 hours
2 days  2 days 
 48 hours
1 - day
“Days” cancel;
Trick: Keep multiplying by unity!
24 hours 60 min
sec
2 days  2 days 

 60
day
hour
min
2 days  2x24x60x60  172,800 seconds
So now you know ….if you
didn’t know before.
Scientific Notation
Graphs
Unit Conversions