ST 204NAME: ______HR: ______DATE: ______
SCIENTIFIC METHOD
PRACTICE SHEET #3
1. Define dependent variable.
The variable that depends on the independent variable. It is the variable that is measured by the scientist.
2. Define independent & controlled variable.
IV: The variable that is decided upon or changed by the scientist.
CV: Also called “constant”, it is the variable that DOES NOT CHANGE during the experiment.
3. Write the materials for an experiment during which the following equipment is used. (The size of the objets do not correspond.)
ST 204NAME: ______HR: ______DATE: ______
· 100 mL beaker
· 400 mL beaker
· 1 Mortar and pestle
· 1 dropper
· Bag of Crystal salt
· Ring clamp
· Test tube holder
· 5 test tubes
· Test tube rack
ST 204NAME: ______HR: ______DATE: ______
4. You are doing the following questionfor you SF project: If you add more baking soda to vinegar will the reaction always be more impressive? Do you think it would be acceptable to do the experiment only once with only 2 quantities of baking soda?
No, you should perform at least 3 trials (use 3 quantities of baking soda) to insure that your results are reliable.
5. You are at the cottage & you are wondering if the shape of a rock affects how far it will go if all rocks are propelled with the same force.
Say whether the following variables are independent, dependent or controlled (constant).
a) The mass of the rocks. Constant
b) The shape of the rocks. IV
c) The wind. Constant
d) The waves on the lake. Constant
e) The temperature of the rocks. Constant
f) The force with which the rocks are thrown. Constant
g) The distance of the rocks. DV
6. You are at the farm & you are wondering which type of sheep gives the most wool.
Say whether the following variables are independent, dependent or controlled.
a) The razor. Constant
b) The age of the sheep. Constant
c) The type of sheep. IV
d) The amount of wool produced. DV
e) The food of the sheep. Constant
f) The frequency at which the sheep drink water. Constant g) The sheep which produces the most wool. DV (same as c)
7. Before you start a vegetable garden, you want to find out which type of tomato plant gives the greatest amount of fruit. Let’s suppose you want to do an experiment with different types of red tomatoes.
Say whether the following variables are independent, dependent or controlled.
a) The color of the tomatoes. Constant
b) The type of tomatoes. IV
c) The amount of water given. Constant
d) The amount of light. Constant
e) The quantity (mass) of tomatoes harvested. DV
f) The type of fertilizer used. Constant
g) The type of soil. Constant
8. A procedure is always written in numbered steps & the steps always start with a command verb.
9. The title of a table always starts by Table 1: