Welcome to S221 Introductory Physical
Science
IPS
http://www.shs.d211.org/science/ips/ips.htm
Mr. Lederhouse
9/09/02
Turn in HW- Return a signed rules and
regulation sheet on Monday.
TMU – Ginnette,Derek
See Me – Joanna, Kevin, Christina, Nick,
Tony, Darren
Today – Density –Measurement and
metrics- Scientific Process
HW – Metric WS, 2 liter bottle, bring
calculator
An object more dense than a fluid in which it is
immersed will sink
An object less dense than the fluid in which it is
immersed floats
An object with density equal to the density of the
fluid in which it is immersed neither sinks or floats (
neutrally buoyant)
Magic Circle
m
D
V
Density = mass/volume
D=m / V (grams/ml)
V= m/D
m= DV
Density is a property of all matter. For a given
material, the density is a constant (does not change).
Density is the ratio of an objects mass to the space it
takes up (volume). If you take a sheet of aluminum
foil and rip it up, the density of each piece (regardless
of size) is the same as the original sheet, which s the
same for any size sample of aluminum 2.7 g/ml
For water, density = 1 gram/ml
aluminum 2.7 g/ml
alcohol 0.81 g/ml
ice 0.92 g/ml
iron 7.86 g/ml
lead 11.3 g/ml
gold 19.3 g/ml
1 ml = 1 cm3 = 1 cc
Problem Solving Steps
1) ID VARS – identify the Variables
2) Write the correct form of the
equation ( use Magic circle)
3) Substitute values and units into the
equation
4) Calculate the answer with units (NO
NAKED NUMBERS)
5) Check – Does the solution make
sense.
Scientific Process
OBSERVING
Metric Pre-Test Choose the Best Estimate
1. A typical temperature for a July day in Chicago is
a. 31°C
b. 90°C
c. –5°C
2. A typical temperature for a January day in Chicago is
a. 30°C
b. 90°C
c. –5°C
3. A typical room temperature is
a. 0°C
b. 75°F
c. 70°C
4. The freezing point of water is
a. 30°C
b. 15°C
c. 0°C
5. A full size sofa has a length closer to
a. 200 cm
b. 200 mm
6. Chris Farley has a waistline of
a. 120 cm
b. 120 m
7. A boom box has a weight of
a. 300 g
b. 3 kg
8. A normal drinking glass contains
a. 200 ml
b. 200 l
9. How much snow do we need for a snow day?
a. 2 cm
b. 2 dm
c. 2 meters
10. A St. Bernard weighs
a. 75 g
b. 75 kg
Metric Tidbits
1. Ladies, if your measurements were 92-61-90 centimeters,
what kind of response would you expect from the men?
2. A record waist measurement is 300 cm. How does yours
compare?
3. There was once a man almost 3 meters tall. Could we use
him on the basketball team?
4. Would a person with a foot 47 centimeters long be
considered petite?
5. If you weigh 225 kilograms, do you think it's time to diet?
6. There was once a man whose hair was over 79 decimeters
long; how does this compare with Mr. L.?
Metric System
Advantages Three basic units of measure
Length – meter
Mass – grams
Volume – liters
Easy conversions for different sizes using prefixes –
Powers of 10
10 –100-1000-10000….
.1 -.01- .001 - .0001 ….
1. Find your starting stair step (km)
2. Find your finish stair step (cm)
3. Count the number of steps you walk to the finish position (don’t count the step you
start on) and the direction that you moved (Up or Down).
(5 steps down)
4. Use the DRUL (Drool) method.
Move the decimal point the same number of decimal places as the number
of steps that you moved
and move in the direction that you walked. Add zeros as needed.
Down Right Up Left -------> DRUL
1.245 km = 124500.0 cm
K- kilo
1000
H - hecto
100
D - Deka
10
meters
grams
liters
d - deci
1/10 = 0.1
c - centi
1/100 = .01
m - milli
1/1000 = .001