variables
Well planned experiments have how many variables?
three
The first step in the scientific method
State the problem or question
Question or problem: Which growth hormone results in larger cows- hormone x or hormone y?
What would my independent variable be if I conducted this experiment?
The type of hormone
Science is the knowledge of the world around us gained by _______, ___________ , and thinking
observing, experimenting
All other conditions or variables in an experiment that must remain the same
constants
Once I repeat my work what is my final step?
Communicate the work
The makers of brand A mouthwash want to prove that their mouthwash kills more bacteria than the other 4 leading brands of mouthwash. They organize 60 test subjects into 6 groups of 10 test subjects.
What is the dependent variable?
how much bacteria is killed/left over
true or false: A theory is an opinion
false
The ONE thing that the scientist changes. It is “What is being TESTED”
Independent Variable
What happens after I form the hypothesis?
Test the hypothesis
A scientist measures how the weight of a toy car impacts the time it takes to roll down a ramp.
What is the independent variable?
What is the dependent variable?
independent: weight of car
dependent: time it rolled
What do we do if new data and observations do not agree with a accepted theory?
scientists change theories or develop a new theory that explains all observations
This answers the question "What will I be observing or measuring during or at the end of my experiment?“
Dependent Variable
a hypothesis is something that is ________
testable
Larry develops a special marshmallow weight-lifting program for Patrick and SpongeBob. He meets with them once every day for a period of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the regular lotion.
What is the control?
the regular lotion.
What is a scientific theory?
an explanation that is supported by MANY experiments, data and observations. à NOT an opinion
exposed to normal conditions. Used for comparison. Not all experiments have one
Control Group
Why is it important to repeat the work in an experiment?
To make sure the information is credible
Question or problem: Which growth hormone results in larger cows- hormone x or hormone y?
What would be the constants if we conducted this experiment?
where the cow lives
what they are fed
how much hormone is injected
What theory was changed because of new data and observations?
*We discussed this in class
Geocentric and Heliocentric Theory