Bob wanted to investigate the effects of plant fertilizer. He bought three identical plants and gave plant 1 fertilizer every mo
rning; plant 2 fertilizer once a week, and he didn't use any fertilizer on plant 3. Bob watered each plant every morning and set all three plants on the windowsill so they would all have the same amount of sunlight. He measured the height of each plant once a week . He plotted plant height (y-axis)vs time (x-axis) for each plant. What is the independent variable * 1 point
Independent variable in an experiment is the variable that is subject to change or manipulation by the experimenter. In this experiment, Bob wanted to investigate the effects of plant fertilizer. Bob sets up the experiment by applying the fertilizer to each plant at DIFFERENT TIMES i.e. plant 1-every morning, plant 2-once a week, plant 3-never.
Based on this, it is obvious that the independent or manipulated variable is the TIME at which he applied the fertilizer. On the other hand, the dependent or measured variable is the height of the plants.
