Physical Science Study Guide Scientific Method & Metric System Online Practice Test: http://www.quia.com/quiz/4395297.html Scientific Method: 1. List the 5 steps of the scientific method (in the correct order)
Observation Hypothesis Experiment Data Analysis/Conclusion
2. What is an inference?
An attempt to conclude that something “causes” something to happen You always need to test it out to be sure
3. A Hypothesis always has two key words, what are they?
If and Then
4. What is the purpose of an experiment?
To Test a hypothesis
5. There is actually a hidden 6th step to the scientific method, what is it?
Repeat your work
6. Step 3 of the Scientific Method has two groups, what are they and how do they differ?
Experimental Group (contains the independent variable – the “thing” you are testing Control Group (use as a comparison group)
7. There are two different variables found in an experiment, what are they, which group are they found in.
Independent Variable (found only in Experimental Group) Dependent Variable (found in both groups, Control and Experimental groups – it is what is being measured – the data)
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8. What is another name for the Dependent Variable?
The data (what is being measured, what is being counted)
9. Identifying different parts of an experiment (Sponge Bob!) At the lab areas are several different experiment setups for you to look at and attempt to identify different parts of an experiment (these are also online, on the practice test) (see below for answer key to these scenarios) Metric System: 1. What is the official name of the metric system? (hint- it is a French name)
Le Systeme International d’Unites (SI system)
2. What is the base unit and symbol for each quantity: Length, Mass, Volume, Time and Temperature.
Length = meter (m) Mass = Kilogram (kg) Volume = Liter (L) Time = Second (s) Temperature = Celsius (°C)
3. Have the “King Henry” Table copied to the index card (one side) and on the other side any other relationships you may need.
You may use your handout that I gave you. It should be in your folder
4. Be able to read and report a measurement from a ruler, graduated cylinder and triple beam balance. (Example problems will be in the back lab area and online)
5. What is the math formula for calculating volume of a cube?
Volume of a cube = L x W x H
6. What is a meniscus and how do you deal with it when reading a graduated cylinder?
The curve that the water line forms in a graduated cylinder. You always read from the bottom of the meniscus
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7. Explain how you would get the volume of an object, like a golf ball, by using water displacement.
1. fill a graduated cylinder with a set amount of water 2. place the object in the graduated cylinder and measure the new water level (this is assuming the object will sink in water) 3. Subtract the difference of the water levels to determine the object’s volume.
8. What is the formula for density?
D=M V
M = mass V = volume
9. In density, mass and volume should be measured in certain measurement units. What are they?
Mass = grams Volume = mL or cm3
10. If I give you certain substances, with their density values, know how they would stack in a container (like a graduated cylinder). Check out the example problem in the lab area or online)
I would look at my Density quiz also Remember the object with the largest density value will sink towards the bottom and the lightest will float
11. What is viscosity? How does temperature affect viscosity?
Viscosity is the resistance of an object to flow Temperture increases, the viscosity will decrease
12. What is the relationship to water in terms of its mass, volume and density?
1g = 1mL = 1cm3
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13. Know the difference between Accuracy and Precision. (You might want to have a picture of the bull’s eye targets I did in notes)
Accuracy= how close you are to the true measurement Precision is degree to which an instrument or process will repeat the same value Accuracy and Precision Illustration Accurate
Not Accurate
Not Precise
Not Precise
Not Accurate
Accurate
Precise
and Precise
14. What is the Atlantic-Pacific rule for figuring out significant digits?
•Atlantic-Pacific Rule
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15. Workout the significant digit problems
See problem answer sheet below
16. Be able to workout the dimensional analysis problems (online and in lab area)
See problem answer sheet below
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Study Guide Problems Density: (be sure to show your work)
River Rock Golf Ball Water
Mass 16g
Volume 6mL
25g
20cmj
18g
18ml
Density
Significant Digits: (How many?) 1. .00058 mm ,;( 2. 459800021000 g 9 3 .. 00580 cm 3 4. 23.89 ml 4 5. 10490 cg Lf
Dimensional Analysis: (show your work!) 1. 56g =
Kg
3. 12.5 inches= 5. 689g =
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2. 3472mm = cm
lbs
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Answers for Question 9 in the Scientific Method Section
Krusty Krabs Breath Mints Mr. Krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath to try this new breath mint. He had fifty customers (Group A) eat a breath mint after they finished eating a crabby Patty. The other fifty (Group B) also received a breath mint after they finished the sandwich, however, it was just a regular breath mint and did not have the secret ingredient. Both groups were told that they were getting the breath mint that would cure their bad breath. Two hours after eating the crabby patties, thirty customers in Group A and then customers in Group B reported having better breath than they normally had after eating crabby patties.
1. Which group is the control?
2. What is the independent variable? 3. What is the dependent variable?
Group B, regular mint breath mint with secret ingredient number of people who reported having better breath
4. What would the conclusion be for this experiment? No difference between breath mints, same number in both groups reported better breath
SpongeBob Clean Pants Sponge bob noticed that his favorite pants were not as clean as they used to be. His friend Sandy told him that he should try using Clean-O detergent, a new brand of laundry soap she found at Sail-Mart. SpongeBob made sure to wash one pair of pants a total of three times, the pants washed in the Clean-O detergent did not appear to be any cleaner than pants washed in plain water 1. What was the problem SpongeBob wanted to investigate?
If Clean-O detergent is better at cleaning than just using plain water. 2. What is the independent variable? 3. What is the dependent variable?
Clean-O detergent how clean the pants were after washing
4. What would the conclusion be for this experiment? Don’t waste money on Clean-O detergent, washing in plain water is just as good
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Patty Power Mr. Krabbs wants to make Bikini Bottoms a nicer place to live. He has created a new sauce that he thinks will reduce the production of body gas associated with eating crabby patties from the Krusty Krab. He recruits 100 customers with a history of gas problems. He has 50 of them (Group A) eat crabby patties with the new sauce. The other 50 (Group B) eat crabby patties with sauce that looks just like new sauce but is really just mixture of mayonnaise and food coloring. Both groups were told that they were getting the sauce that would reduce gas production. Two hours after eating the crabby patties, 30 customers in group A reported having fewer gas problems and 8 customers in group B reported having fewer gas problems.
1. Which group is the control?
Group B
2. What is the independent variable? 3. What is the dependent variable?
new sauce number of people who reported having fewer gas problems
4. What do you thing Mr. Krabbs’ conclusion will be? New sauce reduces gas (30-8)
Slimotosis Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweed on the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp. After a week of treatment, the slime is gone and Gary’s shell smells better.
None. There was not 2 groups created for this
1. Which group is the control? experiment.
2. What is the independent variable? None. SpongeBob tried to have 2 IV (seaweed and Dr. Kelp) in his experimental group. You can only test for one at a time.
3. What is the dependent variable?
None (should have been if slimeotosis disappeared)
4. What would the conclusion be for this experiment? Can not make much of one. Was it the seaweed or Dr. Kelp that cured Gary’s slimeotosis? We won’t know since we the experiment was not done correctly
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Marshmallow Muscles Larry was told that a certain muscle cream was the newest best thing on the market and claims to double a person’s muscle power when used as part of a muscle-building workout. Interested in this product, he buys the special muscle cream and recruits Patrick and SpongeBob to help him with an experiment. Larry develops a special marshmallow weight-lifting program for Patrick and SpongeBob. He meets with them once every day for a period of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the regular lotion.
1. Which Person is in the control?
2. What is the independent variable?
SpongeBob
Time
Patrick
Sponge Bob
Initial Amount
18
5
After 1 Week
24
9
After 2 Weeks
33
17
special muscle cream
3. What is the dependent variable? Recordings in the table 4. What should Larry’s conclusion be? Special Muscle cream did not double the person’s muscle power.
Microwave Miracle Patrick believes that fish that eat food exposed to microwaves will become smarter and would be able to swim through a maze faster. He decides to perform an experiment by placing fish food in a microwave for 20 seconds. He has the fish swim through a maze and records the time it takes for each one to make it to the end. He feeds the special food to 10 fish and gives regular food to 10 others. After 1 week, he has the fish swim through the maze again and records the times for each. What was Patrick’s hypothesis?
1.49
1.34
1.48
1.41
Fish that eat micro waved food become smarter
Which fish are in the control group? Regular food What is the independent variable? What is the dependent variable?
Special food - micro waved Time through the maze
Look at the results in the charts. What should Patrick’s conclusion be
Hypothesis was true,
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Squidward’s Symphony Squidward loves playing his clarinet and believes it attracts more jellyfish than any other instrument he has played. In order to test his hypothesis, Squidward played a song on his clarinet for a total of 5 minutes and counted the number of jellyfish he saw in his front yard. He played the song a total of 3 times on his clarinet and repeated the experiment using a flute and a guitar. He also recorded the number of jellyfish he observed when he was not playing an instrument. The results are shown in the chart. What is the independent variable? music What is the dependent variable? Number of jellyfish What should Squidward’s conclusion be? Jellyfish like music Are the results reliable? Why or why not?
No. Too many groups – remember Magic number is 2
Super Bubbles Patrick and SpongeBob love to blow bubbles! Patrick found some Super Bubble Soap at Sail-Mart. The ads claim that Super Bubble Soap will produce bubbles that are twice as big as bubbles made with regular bubble soap. Patrick and SpongeBob made up two samples of bubble solution. What did the Super Bubble ads claim? One sample was made with 5 oz. of Super Bubble Soap and 5 oz. of water, What is the independent variable? What is the dependent variable? while the other was made with the same amount of water and 5 oz. of Look at the results in the chart. regular bubble soap. Patrick and SpongeBob used their favorite bubble a. Calculate the average diameter for each wands to blow 10 different bubbles bubble solution. and did their best to measure the Super Bubble = ______ cm Regular Soap diameter of each one. The results are = ________ cm b. What should their conclusion be? shown in the chart Are the results reliable? Why or why not?
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What did the Super Bubble ads claim? a. Calculate the average diameter for each bubble solution. Will make bigger bubbles 15.1 What is the independent variable? Super Bubble = ______ cm The super bubbles
11.5 Regular Soap = ________ cm
What is the dependent variable? b. What should their conclusion be? Diameter of bubbles Hypothesis incorrect Look at the results in the chart. Are the results reliable? Why or why not? Yes, there were only two groups in the experiment
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