The Problem Ex What paper towels absorb better
• The Problem • Ex: What paper towels absorb better? How often should you water the plant for the best growth? How many drops of water will fit on a penny? How many glasses of water would it take to fill up a tea pitcher?
• • Example: I think that if I water the plant everyday, then it will grow taller than if I water it once a week.
n _________ n n n You use all five of these to gather information
n
• • __________ • • Trick to remember Variables: • _________
• • Example: You have two plants that are both in the same pot, with the same amount of soil, the same amount of seeds and have the same amount of water. You place one in front of the window and the other in a closet. After two weeks you measure to see the growth of each of the plants.
• • • Example: You have two plants that are both in the same pot, with the same amount of soil, the same amount of seeds and have the same amount of water. You place one in front of the window and the other in a closet. After two weeks you measure to see the growth of each of the plants.
• • • Example: You have two plants that are both in the same pot, with the same amount of soil, the same amount of seeds and have the same amount of water. You place one in front of the window and the other in a closet. After two weeks you measure to see the growth of each of the plants.
1. A controlled experiment works with ______________. If several variables were changed at the same time, the scientist would not know which variable was responsible for the observed results. 2. A experiment is based on the comparison between a ______ with an ____________. These two groups are identical except for one factor. • The controlled group serves as the comparison. It is the same as the experiment group, except that the one variable that is being tested is removed.
Example: In order to test the effectiveness of a new vaccine, 50 volunteers are selected and divided into two groups. One group will be the control group and the other will be the experimental group. Both groups are given a pill to take that is identical in size, shape, color and texture. Describe the control group. Describe the experimental group. What variables are kept constant? What variable is being changed?
There are two types of data: Quantitative data are: Qualitative data are:
Recording and Analyzing Results 1. 2.
n n n
Drawing Conclusions
Forming a Theory A theory Theory: A theory is supported by considerable evidence.
n n n. Example: My theory is that everyone in this class will get an A+ on their first test
• Example: Law of gravity …what goes up will come down…(happens every time)
- Slides: 21