Question

Which is the independent variable in this experiment?



Which is the dependent variable in this experiment?



Which is a controlled variable in this experiment?

Answer 1

I don’t see the experiment you mean — could you paste the procedure or a short description? Then I can pick out the independent, dependent, and controlled variables for that specific case.

Meanwhile, here’s how to identify them and a few examples:

Definitions
- Independent variable (IV): the thing you deliberately change or vary between groups or trials.
- Dependent variable (DV): the thing you measure or observe; it depends on the IV.
- Controlled variables (controls): things you keep the same so they don’t affect the result.

How to identify them in any experiment
1. Ask “What did the experimenter change on purpose?” → IV.
2. Ask “What did they measure to see the effect?” → DV.
3. Ask “What else could affect the DV that they needed to keep constant?” → controlled variables.

Examples
- Plant growth vs fertilizer amount:
- IV: amount (or type) of fertilizer
- DV: plant height or biomass
- Controlled: light level, water amount, soil type, pot size, temperature, plant species
- Effect of study time on test score:
- IV: minutes of study
- DV: test score
- Controlled: test difficulty, environment, study material, time between study and test
- Effect of temperature on enzyme activity:
- IV: temperature
- DV: reaction rate (e.g., product formed per minute)
- Controlled: enzyme concentration, substrate concentration, pH, assay volume

Send the experiment details and I’ll label the IV, DV, and at least one controlled variable for you.