# Welcome to 8th Grade Physical Science Classroom Rules R-E-S-P-E-C-T! Respect YOURSELF. Respect YOUR CLASSMATES. Respect YOUR MATERIALS. Respect YOUR TEACHER. Before doing anything T-H-I-NK!

T- Is this true? H- Is this helpful? I- Is this inspiring? N- Is this necessary? K- Is this kind? What is the scientific method? a series of steps that scientists use to answer questions and solve a problem

Here we identify the steps of the scientific method by IGHEAD: I: IDENTIFY THE PROBLEM(Ask questions and make observations) G: GATHER BACKGROUND INFORMATION H: HYPOTHESIS E: EXPERIMENT A: ANALYZE DATA D: DRAW CONCLUSION Observations

any use of the senses to gather information Two types: Qualitative: No numbers. Example: The litmus paper turned blue when a drop of the solution was added to it. Quantitative: Numbers, measurements, etc. The toy car travelled 15cm. Identify the Problem

Questions help you narrow and focus investigation and identify what you are trying to find out. There are 3 ways to ask a question: What factors cause the sky to be blue. What is the relationship betweenPepsi carbonation levels and Coca-cola carbonation levels? What is the effect of cigarette smoke in the progression of lung cancer? Gather background information

RESEARCH! See what other people already know. This will help you make the best possible hypothesis! Hypothesis possible explanation or answer to a question; MUST BE TESTABLE Formulate your hypothesis using the IF, THEN model. The IF part is what you are doing The THEN part is what will happen

Ex: If study time is increased by 10 minutes every night, then grades will improve. *A note on honesty: Sometimes it is tempting to skew your data to help it match your hypothesis. Please never do this. You will never be counted wrong for having a hypothesis that is not supported; however, you will have HEAVY deductions if I believe you falsified your data to match your hypothesis.* How to write a hypothesis! If the independent variable changes then the

dependent variable changes . Always write your hypothesis in the third person (no I or you statements). Before we can get to hypotheses, lets talk variables Variable: something that can change in an experiment. Most commonly known as the factor/thing being tested in the experiment.

Independent variable? Dependent variable? Control variable? EXAMPLE The higher the temperature of water, the faster an egg will cook. Independent variable? Dependent variable?

EXAMPLE The time it takes to run a kilometer depends on the amount of exercise a person gets. Independent variable? Dependent variable? EXAMPLE The more you water the grass, the taller it will grow.

Variables? Independent Variable? Dependent Variable? EXAMPLE More bushels of potatoes will be produced if the soil is fertilized more. Variables? Independent Variable?

Dependent Variable? Control Variable Revisited Control Variable (CV): A variable that is NOT changed. It is kept the same throughout and is often the most NORMAL situation. You compare the DV results to the CV results. Look for words like same and constant for the control variables. Example: Students of different ages are given the same puzzle to assemble. The

puzzle assembly time is measured. Independent variable? Dependent variable? Control variable? Analysis In order to understand data collected it must be analyze to determine if it supports the hypothesis.

Analysis can be done graphically (bar charts, histograms, scatter plots), through tables, mathematical calculations, qualitative data, etc. Some mathematical ways to analyze data include finding the mean, mode, and median of a data set. Analysis Contd We have to be able to convert numbers from integers to decimals to percentages to fractions. We must also be able to preform metric conversions

(e.g. meters to centimeters) CONVERSION: King Henry Doesnt Usually Drink Chocolate Milk: (Kilo , Hecto , Deca , basic Units (m,L,g), Deci [0.1], Centi [0.01], Milli [0.001]) Ex. 45.76kg = ______________ g *We will revisit basic units and how to measure matter including grams, liters, grams, etc. in the next unit.* Tables and Variables

Tables: When creating data tables and graphs, the placement of the IV and DV is important. Title: Time to assemble a puzzle based on age Independent variable: columns Dependent variable: rows Independent 5

variable (Age) Dependent Variable 10 (time to assemble) 10 20 5

1 Graphs and Variables Students of different ages are given the same puzzle to assemble. The puzzle assembly time is measured. Independent variable goes on the x-axis. Dependent variable goes on the y-axis. Lets make the graph together!!!

Conclusion Three types of conclusions Supports the hypothesis Does not support the hypothesis Need more information Regardless of the out come you must explain

Communicate Results Writing them up in a science journal Submitting them to a respected online magazine NEVER by word of mouth (telling people) Activity Grab a partner and make observations about your partner/ the classroom/ your immediate environment. Findings can be qualitative or quantitative.

BELL WORK What is matter? Matter Matter: physical substance in general that which occupies space and possess mass.

YOU occupy space! YOU possess mass! YOU MATTER! Types of Measurements A. B. C. D.

E. F. G. Length Volume Mass Weight Time

Temperature Density Length Definition: The distance from one point to another point. Base unit: meter (m)

Measuring tool: metric ruler Volume Definition: The amount of space a substance occupies. Base unit: liter (L).

Measuring tools: Regular solids: metric ruler Liquids: graduated cylinder Mass Definition: The amount of matter in a substance. Base unit:

gram (g) Measuring tool: Balance Weight Definition: A measure of gravitational force on an object. Unit:

newton (N). Measuring tool: scale Time Definition: How long an event takes to occur. Unit:

second (s Measuring tool: clock (stopwatch) Temperature Definition: The amount of kinetic energy a substance has. SI unit: Kelvin (K)

Measuring tool: Thermometer Density Definition: How compacted the matter is in a substance. Units: g/mL, g/cm3, kg/m3. *Density is a derived unit (it is made up of other types of measurement).* Equation: D = m / v

*Objects float if their density is less than the density of the fluid they are in.*