PROLOGUE:OBSERVATION AND MEASUREMENT

UNIT 1 – TEST REVIEWUNIT 1 – TEST REVIEW

All formulas are on page 1 of the ESRT

Rate of ChangeRate of Change

DensityDensityAll number answers must have a unit

eg. 500 m/sec. NOT 500All number answers are rounded to the

nearest tenth (example: 0.1g)

Observation vs. Inference

Observation – use of one or more of your five senses (taste, touch, hear, see, smell) Eg.: The rock is round and heavy.

*If the characteristic is measurable (heavy), it is considered to be an observation.

Inference – an educated guess about an observation. Eg. The rock is old.

Prediction

Prediction – an inference based on an observation that may indicate what will happen in the future.

Eg.: A meteorologist makes a prediction of the next day’s weather (a weather forecast). A weather forecast is a prediction of weather that will happen in the future.

Classification

Grouping of similar objects or events based on similar observable properties.

Classification

Grouping of similar objects or events based on similar observable properties.

Solids Liquids Gases

Interface

The boundary between regions having different properties.

Graphs – 4 types

Direct: both variables increase Indirect: independent variable increases,

dependent variable decreasesCyclic: dependent variable (vertical axis)

increases, then decreases in a repeated pattern

Static: dependent variable remains the same – no change

Measurement

3 basic units of measurement:

meter (length) m

liter (liquid volume) l

gram (weight / mass) g

Mass vs. Weight

Mass and weight are NOT the same thing. They are two different concepts, but are related to each other. Here’s how…

massmass (a measure of the amount of molecules contained in an object) – grams.

weightweight (a measure of the pull of gravity

on an object) – kilograms.

Scientific Notation – Exponents

Very small or very large numbers are expressed in scientific notation form to make it easier to read. M x 10n

M is any number between 1 and 10Example: 27,508 = 2.7508 x 104

Negative exponents indicate a value less than 1 (eg. 0.00875 = 8.75 x 10-3)

Positive exponents indicate a value greater than 1 (eg. 2500 = 2.5 x 103)

Metric Conversion

To convert to a larger unit, kilo 1000.

move the decimal to the left hecto 100.

deka 10.

metermeter literliter gramgram 1.

deci .1To convert to a smaller unit, centi .01

move the decimal to the right milli .001

Metric Conversion – how to do it!

To convert to a larger unit, move the decimal to the left.

To convert to a smaller unit, move the decimal to the right.

milli milli –– centi centi –– deci deci –– 1.01.0 –– deka deka –– hecto hecto –– kilo kilo

smaller units larger units

Example: 1.0 m = 100.0 cm = 1000.0 mmConvert 2000 cm to _____km? _____

Metric Conversion – Practice!

3.5 x 10-3 = __________

a. 0.0035 b. 3.5 c. 350 d. 3500805,000 = ___________

a. 8 x 105 b. 8 x 106 c. 8.05 x 105

142,800 km = ____________29.5 years = __________4.6 billion years ago = ___________5900 million km = _____________

Equation – ESRT, pg. 1

Rate of Change – How long it takes for a given change to occur (measurable value).

Rate of Change = change in value

time

Eg.: The rate of change of the hot water in the beaker decreased after two hours.

Equation - ESRT, pg. 1

Rate of ChangeRate of Change

Rate of change = change in field value

time

Example: 200 ft. – 100 ft. = 20 ft./min.

5 min.

Equation – ESRT, pg. 1

Density Density – The relationship between between the mass and volume of a substance

Density of a substance = mass (g)

volume (cm3)The density of an object remains the same, unless

heat or pressure are applied. Heat (temperature) decreases density. Pressure increases density. Size or shape do not change the density.

Equation – ESRT, pg. 1

DensityDensity

Density of a substance = mass (g)

volume (cm3)

Example: 50g = 25g/cm3

2cm3

Liquid Density

In a graduated cylinder, the most dense substance (greatest density) is on the bottom, and the least dense (least dense) substance is on the top.

least dense

most dense

50ml 55ml

Water Displacement