Scientific Investigation

Scientific Investigation

Graphing

IV & DV on Graphs

The IV is graphed on the X-axis

(If time is a variable, it is generally on the x-axis)

The DV is graphed on the Y-axis

The effects of absences on test scores

• What is the IV?

• Absences

• What is the DV?

• Test scores

• What might be a hypothesis for this experiment?

• If student absences increase, then test scores will decrease. :(

Multiple Choice

What is the IV and what is the DV?

• IV: depth of plant, DV: depth of water

• IV: number of bubbles produced, DV: number of minutes

• IV: Depth of water, DV: number of bubbles produced

• IV: Type of plant, DV: Temperature of water

Multiple Choice

What is the IV and what is the DV?

• IV: light intensity, DV: type of plant

• IV: Color of light, DV: light intensity

• IV: Color of light, DV: Rate of photosynthesis

• IV: Light Intensity, DV: Rate of photosynthesis

Multiple Choice

Which is a possible hypothesis for this experiment?

• If the intensity of the light increases, does the color change?

• If the rate of photosynthesis increases, then the plants don't do photosynthesis

• If the light intensity decreases, then the rate of photosynthesis decreases.

• If the color of the light changes, then the rate of photosynthesis changes.

Bar Graphs

• IV on the X-axis; DV on the Y-axis

• Used when one of the variables is a category instead of a number

Sometimes the IV is in the key

Sometimes the IV is in the key

Multiple Choice

What is the IV & what is the DV?

• IV: Plant type, DV: Height of plant

• IV: earthworms, DV: Plant growth

• IV: Plant growth, DV: Plant type

• IV: Photosynthesis, DV: Plant type

Multiple Choice

What is a possible hypothesis for this investigation?

• If the number of earthworms increases, then the plant height increases.

• If the plant height increases, then the number of earthworms decreases

• If the earthworms increase, the number green bean plants will decrease

• If tomato plants increase, the number of green bean plants will increase.

Multiple Choice

Which is a valid conclusion based on this data?

• When tomato plants are grown, green bean plants cannot grow.

• Plants grow taller without earthworms in the soil.

• Earthworms increase the number of radishes.

• When earthworms are present, plants grow taller