Physical Science Notes



Physical Science Notes

Unit 1

Scientific Rules and Measurements

What is Science?

Physical is just on branch of Science. Science is observing, measuring, studying, and experimenting in order to determine the nature of the world we live in (how it works). Science tells us what it does, not what it ought to do.

The Nature of Science

Science begins with a Question. Students are supposed to write down three scientific questions about the world that they would like to answer this year.

The Scientific Method

Ask a question, Investigate, Set up an experiment. Sketch a picture, make data tables, and devise a procedure. Make observations and record data. Evaluate results. Sometimes unexpected results lead to new discoveries!

Science and Technology

If science is learning how things work, then the application of science ideas to everyday life is called; TECHNOLOGY. The students were asked to give an example of technology.

Physical Science deals with study of physical quantities.

• Physical Quantities- measure to quantify. Ex. Mass. Volume, density

• Physical Properties- Qualities or attributes of object

• Description has both: Number- how much of a quantity. Units-well defined reference amount.

English Customary System of Units

Most common system in the USA is Foot, pound, and second. Changes in parts of the world, and now it is in terms of metric. This is not common in the rest of the world. A worldwide system is needed for science, trade industry.

The Scientific Method (Optical Illusion) and Metric System Notes worksheet was given out.

Metric System (1791)

• Based on easily reproduced standards

• Quantities measured as number and unit

• Meter, Gram, Second

Units and Standards

• What is a standard?

1. Historically things such as hands and feet were used to make measurements.

• Why would we use standards?

2. So we all know what the specific measurement is.

• Why might hands and feet be a problem?

3. Peoples hands and feet are different sizes.

Standard- An exact measure that people agree to use universally.

• A quantity that doesn’t change over time.

• Using a standard allows for comparison

The SI System

The SI system is a standard system used throughout science and the world. A lot of the units are the SI system is from the metric system- so a lot of people use the terms SI and metric interchangeably.

What are the SI standards for Length, Mass, and Time?

• Length- The meter

• Mass- The kilogram

• Time- Second

For larger or smaller measurements we just add prefixes

Prefix Multi. Factor

Kilo 1000

Hecto 100

Deka 10

Base Unit

Deci 0.1

Centi 0.01

Milli 0.001

Using Meters as an example

1 Kilometer = 1000 meters

1 Hectometer = 100 meters

1 Dekameter = 10 meters

Meter (Base Unit)

10 Decimeters = 1 meter

100 Centimeters = 1 meter

1000 Millimeters = 1 meter

So how do we remember those prefixes?

King Henry Doesn’t Usually Drink Chocolate Milk (First letter of each word lines up with prefixes)

kilo, hector, deka, unit, deci, centi, milli

Standard system vs. Metric System

|Measure |Standard |Metric |

|Distance - length |Inches |Millimeter |

| |Feet |Centimeter |

| |Yards |Meter |

| |Miles |Kilometer |

K H D U D C M

Changing from one metric unit to another is called Metric Conversion

U is the space where meter, liter, of gram, belongs.

To change from one metric unit to another, we simply move the decimal point either to left or to right.

For ex.

0.254 km = _________m?

K-H-D-U is 3 places to the right

0.254km = 245m

Ex. 2

K H D U D C M

30cm= __________hm

C_D_U_D_U is 4 places to the left

30cm = .0030hm

14Km = ________cm

K_H_D_U_D_C is 5 places to the right

14Km = 1,400,000cm

Scientific Measurement

Linear Measurement

• Measure length or distance

• Metric Base Unit- Meter

• Tools- ruler, meter stick

Volume Measurement

• Measure the amount of space occupied by an object

• Metric Base Unit- Liter

• How to measure:

1. Regular shaped objects (i.e. a cube)- measure length, width and height (multiply all 3).

2. Irregular shaped objects- use water displacement method.

Side Note: 1cm3 = 1ml

Mass

• Measure the amount of matter

• Metric Unit- gram

• Tools- balance

Weight

• Measures the force of gravity on an object

• Metric Base Unit- Newton

• Tools- scale

Mass does not change- Weight can change

• You found a rock and want to know the volume of it. How would you measure the volume? Answer: Water displacement method.

The Scientific Method

• What is the scientific method?

It is process that is used to find answers to questions about the world.

• Is there only one scientific method?

No, there are several versions of the scientific method. Some versions have more steps, while others may have only a few. However, they all begin with the identification of a problem, or a question to be answered based on observations of the world around us and provide a method for conducting and analyzing an experiment.

• What is a hypothesis?

It is an educated guess based on observations and you knowledge of the topic.

• What is date?

It is the information gathered during an experiment. Ex. Measurements, observations

• For the Scientific Method we identify the problem.

What do you want to know or explain? Use observation.

• Form a hypothesis

What do you think will happen? Develop a procedure for a reliable experiment and address safety rules.

• Perform an Experiment

Follow the steps in your procedure to perform your experiment. Record data and observations.

• Analyze the Data

Is the data reliable? Does your data and observations from the experiment support your hypothesis?

• Is your data inaccurate or the experiment flawed?

Is the experiment flawed?

• Id so… Modify the experiment.

• Communicate the results.

Write a conclusion that summarizes the important parts of your experiment and the results.

Graphing Etiquette

• All graphs must have a title

• All graphs must have labels on axes (with units!!)

• All graphs with more than one set of data must have a legend (key).

• The independent variable is always on the x-axis while the dependant variable is on the y-axis.

Mass, Volume, and Density

Mass

• Mass is a measurement of the amount of matter something contains.

Weight

• Weight is the measurement of the pull of gravity on an object.

How are weight and mass different

• Mass is measured by using a balance

• Weight is measured on a scale.

• The mass of an object doesn’t change when an object’s location changes.

• Weight, on the other hand does change with location i.e. on the moon.

Volume

• The amount of space occupied by an object.

Measuring VOLUME of a liquid

• If you wanted to measure 25ml of water, you want instrument would you use?

Measuring VOLUME of a solid

• If the shape is a box you can use a ruler, measure the sides and calculate:

• Volume: = length x width x height

• Other shapes have their own equations to calculate volume.

Steps to water Displacement

1. Pour water into a graduated cylinder and note measurement of water

2. Add object into the water

3. Measure the difference of the water.

One Cubic centimeter = one milliliter

• 1cm3 = 1ml

Density

• Density is a measure of how much mass (g) is contained in a given unit volume

(cm3 or ml)

• Gold is very dense- it feels very heavy for its size.

• Each substance has its own density.

• A larger amount will still have the same density.

• You can use density to identify an unknown metal.

• Density = mass / volume, mass = density x volume, volume = mass / density

Graphs

Graphs

• Graphs are great ways to capture and display data (information).

Types – Line, bar graphs, and pie chart

Graphs

• Line graph show trends of continuous change.

• Bar graph is used to display information collected by counting

• Pie chart is used to show how some fixed quantity is broken down into parts.

Look up examples for all three graphs.

Line Graphs

• Shows variation through time

• Can be used to show comparison too.

Pie Graph

• Shows how a whole is broken into parts

Elements of a good graph

• Axes labeled with units

• Use the available space

• Title

• Legend

• Neat

Creating a graph

1. Draw and label the x and y axis

2. Label what variable is on each of the axis.

3. Plot the data points that you collected on the graph.

4. If it is a line graph, connect the points with as smooth a line as possible.

Line Graph note:

• In a line graph sometimes when you connect the dots the line does not make since or show any valuable information. This is when you use a line of best fit, which is a visual average straight line. This is also called a trend line.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download