Lesson 013 Learning Goal: (You should be able to…) Identify independent variables in parachute design Select an independent variable to identify a pattern or relationship Write an hypothesis Success Criteria: (Can you …) Write a testable statement in a particular format? With variables, prediction and reason?

How to organize lesson 013 The lessons Agenda was: Describe the characteristics of an hypothesis Create hypotheses for particular scenarios

Vocabulary Compressed air Momentum Velocity Terminal velocity Drag Opposing forces Gravity Canopy Payload Hypothesis Independent variable Dependent variable Baseline Control

Write To Think 013 Remember: Do this on lined paper or in Lab notebook 1.What is an “Independent variable” ? 2.List three possible independent variables for the parachute. 3.Why should you only change one independent variable in your new experimental ‘chute? 4.Why should you keep the two paper clips the same (constant)?

Parachute Investigation How dos the desgn of a parchute affect the velocty of its descnt?

Variables and constants Independent variable: It could change, it’s manipulated, scientist changes something (IV) Dependent variable: it could change, it responds to something, scientist collects data (DV) Constants (C) are not VARIABLE!!! They stay the same every time.

What is a hypothesis? Select the letter or letters that you think are descriptions of an hypothesis or part of a hypothesis. Compare AND discuss ‘Answers’

‘Answers’. A Hypothesis includes/can be/is.. AYES BYES CNO ?? DNO EYES FNO GYES HNO INO JNO KYES LYES MYES ?? NNO

What is a hypothesis? Purpose and characteristics – Based on observations – Suggest relationships – Predictive – Tentative explanation (possible but not sure) – Testable – Help an investigation – Supported or not supported BY DATA – Come from questions – Logical and creative and imaginative They are : – NOT a question – NOT provable, true or correct, false or incorrect – NOT an educated guess – NOT always necessary in science! – NOT always used!

An hypothesis is … An hypothesis is a tentative (possible, but not sure) explanation that can be tested and is based on observation and/or scientific knowledge such as that gained from doing background research.

Hypothesis Template If _______________________ ________________________ is related to ______________ ________________________ then ____________________ ________________________ because __________________ _________________________

Hypothesis Template If (independent variable) is related to (the dependent variable) then (make a specific prediction) because (scientifically explain why you think the change in the independent variable will alter the dependent variable)

Hypothesis practice Read the scenario Identify and write down the IV on the template Identify and write down the DV on the template Complete writing the hypothesis for the scenario using the template First one together … next slide Second one in pairs Third, fourth and fifth on your own.

Hypothesis for Smithers (1) If the type of juice used is related to the productivity of the workers then the workers who drink the special juice will make 33% more stacks of stapled papers because the special juice provides more energy and vitamins to help the workers be faster, more efficient and more focused than without juice.

Hypothesis for Homer (2) If the type of cleaner is related to the appearance of green slime then the coconut juice will completely remove the free slime in 3 days because the coconut juice has a chemical in it (anti fungal) that kills the green slime.

Parachute investigation plan Tues 8/12: Introduction. (Video and reading) Thurs 8/14: Build baseline parachute. Fri 8/15: Create a protocol. Assess and trial and gather data. Assess PSR Thurs 8/21: Analyze. ID Variables.. Fri 8/22: Hypothesis practice. Create a new Hypothesis. Assess. Design new parachute. Build, trial and gather data. Mon 8/25: Build, trial and gather data. Assess PSR Tues 8/26: Analyze. Compare. Assess. Electronic Write up of the conclusion. Thurs 8/28: Electronic Write up of the conclusion. Fri 8/29:Complete and ‘hand in’ conclusion. Assess.

Your Lab Note Book should have.. Parachute Investigation: How does the design of a parachute affect the velocity of its descent? The contents page should have the title and page number reference The first page of the investigation needs a Title (See above) Picture with labels (see Pictures C and A) written a consistent testing protocol so another group could follow it and get similar results. Have a neat labeled diagram of your baseline ‘chute with dimensions etc. a data table for the baseline parachute Data analysis of baseline parachute data (mean time and mean velocity Brainstormed possible variables you might change to help answer the investigative question … see the title!