Variables
A scientist changes the temperature of water and measures how much sugar dissolves. What is the independent variable?
The temperature of the water
A student investigates how exercise affects heart rate.
Identify the independent and dependent variables.
IV: Exercise
DV: Heart Rate
A student tests how fertilizer affects plant growth. Name a control variable
-Type of fertilizier
-Type of plant
-Amount of light plants receive
-Amount of water plants receive
etc...
What is wrong with the following research question?
Does amount of rizz affect how many friends a student has?
It is a closed question
What is wrong with the following research question? How do amount of sunlight and water affect the height of a plant measured over three days?
There is two independent variables
A scientist investigates how light intensity affects photosynthesis.
Plants closer to the lamp become hotter.
Explain why this is a problem.
Temperature becomes a second independent variable and may affect photosynthesis, reducing validity.