Vocabulary
The variable that is changed by the scientist when conducting an experiment is the..
Independent Variable
Question: Which battery lasts longer, energizer or duracell?
Identify the Independent and Dependent variables.
Independent - type of battery
Dependent - how long the battery lasts
Increased sleep will result in higher test grades.
Observation or Inference?
Inference
What effect does crushing ice have on the rate at which it melts?
What step of the Scientific Method is this?
Step 1- Ask a question
The rocks at the beach are smooth and round. They must've got this way by the process of weathering.
Identify the observation and inference in the statement.
Observation - Smooth and round rocks
Inference - Got that way by weathering
Information gathered by using one of the five senses is call a(n)..
QUALitative Observation
Students of different grade levels (elementary, middle school and high school) were given the same puzzle to put together. They were timed to see how long it took to finish the puzzle.
What is the independent and dependent variable in this experiment?
Independent - students of different grade levels
Dependent - time it took to finish the puzzle
The people down the street must be having a barbecue because I hear music but smell something burnt.
Identify the observation and inference in the statement.
Observation - Hear music, smell something burnt
Inference - People having a barbecue
Question: Does putting salt in soil affect plant growth?
Come up with a hypothesis using the "if/then" format.
If I put 1 cup of salt in the soil for 1 week, then the plant will grow 10 cm higher than with no salt in the soil.
During a handshake, you notice the person’s hand has blisters.
Make an inference about your observation.
The person works out at the gym and the blisters are from lifting weights.
The person works outside and the blisters are from handling a shovel, etc.
What in an experiment is left alone, but is included in the experiment to compare your results to?
The control group
Question: Which type of music quiets a baby faster: classical, jazz or rock?
Identify the:
Independent variable
Dependent variable
1 Constant
Independent - Type of music
Dependent - How fast the baby quiets
Constant - Baby
There is a baseball in my driveway and my car's windshield is cracked in 4 places. Someone playing ball must have shattered my windshield.
Identify the QUANTitative observation in the statement.
QUANTitative observation - 4 cracks in windshield
If I expose myself to 5 hours of UV rays outside, then I will increase my risk of getting skin cancer.
What step of the Scientific Method is this?
Hypothesis
Question: Does temperature cause leaves to change color?
If we conducted an experiment to answer this question, what would our independent variable be? Our dependent variable?
Independent: Changing temperature
Dependent: Change in color
Define what the "dependent variable" is in an experiment.
It is the variable that is measured - the result of the experiment.
The Johnson family has decided to try to save electricity (and money at the same time). They were told that they could replace their incandescent light bulbs with special fluorescent bulbs that use less energy. They wonder if it is really worth doing.
If the Johnson's decided to experiment with this, what would be their control? Their independent variable? Their dependent variable?
Control - incandescent light bulb
Independent - fluorescent light bulb
Dependent - how much energy is used
It must have stormed last night because there are large puddles in my backyard and the stream by my house is moving at a speed of 20 mph!
Identify the QUALitative and QUANTitative observations in the statement.
QUAL - large puddles
QUANT - stream moving at a speed of 20 mph
Inference - It must have stormed last night
List the SIX steps of the Scientific Method in order:
Ask a question to solve an observed problem
Do research on the problem
Construct a hypothesis
Test hypothesis and gather data
Analyze data by constructing a graph
Draw a conclusion based on your results
Is acid rain causing a decline of frog populations?
Identify the:
Independent Variable
Dependent Variable
Independent - Acid rain
Dependent - Frog population
Control - Normal rain
What is the difference between an inference and a hypothesis?
An inference is a guess based on observations of what IS happening in the present (ex: The cat in the shelter has straggly hair. It must BE an old cat).
A hypothesis is a guess to predict what WILL happen based on observations. (If someone walks in the shelter and sees the straggly cat, then the cat WILL get adopted).
You've been noticing a green slime forming on the walls of your shower, and the water from the shower is just not getting rid of it. You want to see if adding lemon juice to the water by spraying it on the green slime will get rid of it.
What is the control group in the experiment?
What is the independent variable? The dependent variable?
Control - Water from shower with no lime juice
Independent - Adding lime juice
Dependent - If the slime stays on the wall or not
The principal interrupts class and calls a student from the room.
Make an inference based on this observation.
The student is in trouble.
The data collected during my experiment to find out if lower temperatures provide more oxygen in water shows that if I decrease the temperature of the living conditions of fish, then the fish's respiration rate increases.
What step of the Scientific Method is shown? What 2 things are included in this step?
Step 6- Draw a conclusion
1. Results of the experiment are explained
2. States if hypothesis is correct or not
I want to see which type of fertilizer works best to grow tomatoes. I will set up my experiment by testing 3 types of fertilizers on 3 tomatoes plants which will receive different amounts of water each day for a month.
What is wrong with this experiment?
What is wrong - An experiment should only test ONE variable. The amount of water given to the tomato plants should stay the same. If it is also different, the experimenter wouldn't know if it was the fertilizer or the amount of water that worked the best.