Just A Test
Camilla wonders if walking for 30 minutes each day will lower her overall resting heart rate. Which experiment would be best to test this hypothesis?
a. Walk for 30 minutes each day for a month. Check heart rate at the end of the month.
b. Check heart rate. Walk for 30 minutes. Check heart rate again.
c. Check heart rate and then walk for 30 minutes. Recheck heart rate. Repeat each day for a month.
d. Check heart rate while walking, running, resting, and standing; then compare.
c. Check heart rate and then walk for 30 minutes. Recheck heart rate. Repeat each day for a month.
What are the three types of variables we have talked about?
Independent, dependent, control/constant
How many types of observations are there and what are they called?
2! Qualitative and Quantitative
when someone else (other than the original researcher) carries out an experiment exactly and gets the same results over and over again
Replication
a process of finding the answer to a question using various research methods
Investigation
Some scientists are concerned that television, radio, and newspapers report the outcome of experiments too quickly. What would be the major scientific concern?
a. People may copy the ideas and sell them for profit.
b. Conclusions may be drawn by the public before the results are replicated by other scientists.
c. Other agencies may hear of the results and claim credit for them.
d. The level of scientific research is turned into a media event.
b. Conclusions may be drawn by the public before the results are replicated by other scientists.
Ladybugs are placed in a container where they have a choice of a wet or a dry environment. Researchers record how much time was spent on each side.
What is the Independent Variable?
The environment.
There is a lot of tall and green trees out in the forest. There is also very little noise. What type of observation am I?
Qualitative
a logical interpretation of observations that allows scientists to make claims
Inference
A procedure in which only ONE variable is purposely changed or manipulated in order to see if it has an effect on another variable.
Experiment
Leslie had five beakers. She filled one with a weak base, one with a strong base, one with a weak acid, one with a strong acid, and one with water. She placed a 15-gram piece of iron in each beaker, and left the beakers uncovered on her desk. Three days later, she observed the size of the piece of iron that remained What question was Leslie most likely trying to test?
a. Does iron react most with acids, bases, or water?
b. How quickly does iron react with acids, bases, and water?
c. Does the strength of an acid affect its reaction rate?
d. How does iron combine with the molecules in acids and bases?
a. Does iron react most with acids, bases, or water?
A student wanted to test how the mass of a paper airplane affected the distance it would fly. Paper clips were added before each test flight. As each paper clip was added, the plane was tested to determine how far it would fly.
What is the control variable?
How the paper airplane was made
This type of observation uses words to describe what our senses are telling us.
Qualitative
a representation of a complex object or process used to help us understand a concept that we cannot observe directly
Scientific Model
Investigation or experiment: Testing the growth of a plant using different types of soil.
Experiment
A physicist at a respected research laboratory reports a startling new discovery. Her conclusions are based on data from many repeated trials, however, other scientists are unable to reproduce the results of the experiment. Which statement leads to the conclusion that the original experiment might not be valid?
a. The results were announced to the public.
b. The conclusions were based on multiple repeated trials.
c. The experiment did not include sophisticated equipment.
d. The experiment’s results cannot be replicated.
d. The experiment’s results cannot be replicated.
The higher the temperature of the air in the oven, the faster a cake will bake.
What is the dependent variable?
Time to Bake
This type of observation will have numbers associated with it.
Quantitative
what you are measuring at the outcome. The effect. The results.
Dependent Variable
Investigation
What is our test taking strategy called?
RELAX
A study was done to find if different tire treads affect the braking distance of a car.
What is the independent, dependent and control variable?
Independent: Tire Tread
Dependent: Braking Distance
Control: Car
What's the difference between an observation and an inference?
Observation uses one or more of our sense to gather information.
Inference is a logical conclusion based on observations you have made.
what you are testing to see if it has any effect on the dependent variable. It is the cause.
Independent Variable
Think back to the elephant toothpaste lab, was this an experiment or an investigation.
Investigation! We were just seeing what happen when we mixed the yeast mixture in with everything else.