Science Buddies: "Ask an Expert"

So the confusion continues. I am going over my son's project, making sure it is complete before being submitted. My question is, does a science project need an independent variable ? This project is only measuring the growth rate of hot peppers vs. sweet peppers. Same amount of water, same soil, same sunlight. Everything is the same except the type of pepper. Is the type of pepper the independent variable ? and if so, which one ?

Jason

Pepper type (hot vs. sweet) is indeed your independent variable. It is what we call a categorical variable--e.g. it is different categories.

Hi Jason,

Science Buddies has an excellent page about variables:

https://www.sciencebuddies.org/science- ... bles.shtml

Hope that helps!

Hi Jason,

The other experts have already pointed you in the right direction. I just thought I would add a few details. Since pepper type (hot vs. sweet) is your independent variable (the one you change), it means that growth rate (the one you measure) is the dependent or response variable. The other factors (water, soil, sunlight) were things that could potentially affect your growth rate, so you made sure to control them (make them the same).

Let us know if you have any other questions.

Heather