Identifying Variables Practice Problems

Four groups of rats are first massed and then fed identical diets except for the amount of vitamin A they receive. Each group gets a different amount. After 3 weeks on the diet, the rats' masses are measured again to see if there has been a decrease. Identify the dependent variable.

• Groups of rats

• Diets

• Vitamin A

• Rats' masses

Tags

NGSS.MS-LS2-1

The independent variable is the ONE thing you _____.

• change
• keep the same
• experiment with
• investigate

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, what is the independent variable?

• Type of plant
• Water, apple juice, milk
• Plant growth

What is the dependent variable (effect) is this experiment?

"Does eating breakfast improve test score?"

• eating breakfast or not

• the grade you got on the test

• what time you get up in the morning

• how tasty the breakfast is

What is the independent variable (cause) is this experiment?

"Which type of medium (soil or sand) is best for plant growth?"

• height of plant (cm)

• type of medium (soil or sand)

• amount of medium (soil or sand)

• types of plant

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

What is the dependent variable (effect) in this experiment?

"Do tall people jump further than short people?"

• height of the person

• weight of the person

• how fast the person runs

• how far the person jumps

What is the independent variable (cause) in this experiment?

"Which type of metal, copper or aluminum, conducts heat faster?"

• size of metal

• types of metal

• time it takes to heat up

• shape of the metal

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

Janet wants to see whether drinking coffee will improve productivity (productivity is how much work you get done). What is the independent variable in this experiment (cause)?

• increase productivity

• Having coffee or not

• the brand of coffee

• the time drinking the coffee

A factor or condition that is kept the same is called the

• control variable

• dependent variable

• independent variable

Identify the independent variable:
A study was done to find if different tire treads affect the braking distance of a car.

• The car
• The distance the car took to brake
• The different tire treads
• The driver