Scientific Method. REMEMBER: Quiet Hippos Eat Dark Chocolate Question; Hypothesis; Experiment; Take Data; Form Conclusions

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1 Section 1.1 Scientific Method (pages 4-8) Scientific Method REMEMBER: Quiet Hippos Eat Dark Chocolate Question; Hypothesis; Experiment; Take Data; Form Conclusions 1 P age

2 Predicting and Hypothesizing A prediction is an expectation of what will be observed or what will happen. A prediction is a tentative explanation for an observation or scientific problem that can be tested by further investigation. EXAMPLE Suppose you have made two paper airplanes and you wonder why one of them tends to glide farther than the other one. 1. Start by asking a question. 2. Make an educated guess. After examination, you notice that the wings of the airplane that flies farther are slightly larger than the wings of the other airplane. 3. Write a prediction based upon your educated guess, in the form of an If..., then... statement. Write the independent variable after the word if, and the dependent variable after the word then. 4. To make a hypothesis, explain why you think what you predicted will occur. Write the explanation after the word because. 1. Why does one of the paper airplanes glide farther than the other? 2. The size of an airplane s wings may affect how far the airplane will glide. 3. Prediction: If I make a paper airplane with larger wings, then the airplane will glide farther because... Research Question What is the relationship between the number of Mentos and how high soda will travel? Prediction 2 P age

3 Observations Quantitative Depend on the human senses. Qualitative Measurements that are taken such as mass, time, speed, termperature. You use tools to collect numerical data. How observant are you? This experiment demonstrates your ability to remember details accurately. How accurately do you remember what you have seen? What factors may play a role in what we remember and describe about what we have witnessed? Consider these questions as you do the following activity. You will see a picture on the next slide. Observe the picture for exactly 30 seconds. Look at everything you think might be important. After 30 seconds answer the following questions. Then compare your answers to the picture. 3 P age

4 Observations 1. Is there a car on the street? 2. How many cyclists are on the street? 3. What is written on the plate of the car? 4. What does the sign on the right side of the picture say? 5. What is written on the wall of the apartment to the left? 4 P age

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6 Variables Independent Dependent Control A sixth grader investigates to see if the mass of a toy car will change the distance the car travels after it reaches the bottom of a ramp. The ramp is set at the same height for all the trials. The same car is used each time and only the mass of the car is changed. One trial is just the car with no mass added to it. The car is released at the top of the ramp, not pushed to start it. The distance traveled is always measured in the same units and with the same meter stick. 1. Write a possible and appropriate hypothesis to this experiment. 2. What is the independent variable? 3. What is the dependent variable? 4. What is the control variable? 6 P age

7 Independent & Dependent Variables Problems 1. You want to test a new drug that supposedly prevents sneezing in people allergic to grass. What is the dependent variable? 2. You want to see if playing music makes plants grow taller. What is the independent variable in this experiment? 3. An entomologist (bug scientist) wants to determine if temperature changes how many times a cricket chirps. What is the dependent variable? 4. You want to measure the effect of different amounts of oxygen on the rate of yeast growth. What is the dependent variable? 5. You think that a certain part of your brain is important in memory. To test this, you will remove this part of the brain from rats and see if they remember how to get through the maze. What is the independent variable in this experiment? 6. Orchids were studied to determine if the amount of humidity affected the flowering of these plants. Which of these was the independent variable in this study? Questions #7-10 refer to this experiment: Suzie Q wants to know how different colors of light effect the growth of plants. She believes that plants can survive the best in white light. She buys 5 ferns of the same species, which are all approximately the same age and height. She places one in white light, one in blue light, one in green light, one in red light and one in the closet. All of the ferns are planted in Miracle-Grow and given 20 ml of water once a day for 2 weeks. After the two weeks, Suzie observes the plants and makes measurements. 7. What measurements could Suzy make to determine how different colors of light affect the growth of plants? 8. What is the independent variable? 9. What is the dependent variable? 10. What are the control variables? Challenge Problem Write a scenario like the one above where an experiment is being conducted. Clearly state what you are investigating in your experiment, what variables you would change and what variables you would keep constant to test your experiment. Example Coorporation XYZ wishes to study the correlation between safety training and the number of accidents at various production sites. Those responsible for the training believe that safety training will help reduce the amount of accidents. The numbers of safety training hours work teams receive and the number of accidents each team experiences are recorded for a period of a year after training occurs. 7 P age

8 JoAnna read that certain perfume esters (chemicals) would agitate bees. Because perfume formulas are secret, she decided whether to determine whether the unknown Ester X was present in four different perfumes by observing the bees behavior. She placed a saucer containing 10 milliliters (ml) of the first perfume 3 meters (m) from the hive. She recorded the time required for the bees to emerge and made observations on their behavior. After a 30-minute recovery period, she tested the second, third, and fourth perfumes. All experiments were conducted on the same day when the weather conditions (air, temperature, wind) were similar. Read the following science scenario, then, identify the parts below. 1) Independent Variable Ester X 2) Dependent Variable Time required for bees to emerge from the hive and other behaviors 3) Controlled Variables distance from hive to saucer, same day, air, temperature and wind 4) Write a Hypothesis None of the perfumes contain Ester X 5) Write a Title for the experiment Does perfume agitate bees? Susie wondered if the height of a hole punched in the side of a quart-size milk carton would affect how far from the container a liquid would spurt when the carton was full of the liquid. She used 4 identical cartons and punched the same size hole in each. The hole was placed at a different height on one side of each of the containers. The height of the holes varied in increments of 5 centimeters (cm), ranging from 5cm to 20cm from the base of the carton. She put her finger over the holes and filled the cartons to a height of 25cm with a liquid. When each carton was filled to the proper level, she placed it in the sink and removed her finger. Susie measured how far away from the carton s base the liquid had squirted when it hit the bottom of the sink. Read the following science scenario, then, identify the parts below. 1) Independent Variable Height of hole in carton 2) Dependent Variable Distance liquid spurts from carton 3) Controlled Variables identical cartons, same size hole, same amount of liquid 4) Write a Hypothesis The higher the hole the less distance the liquid with spurt 5) Write a Title for the experiment Does water pressure matter? 8 P age

9 When you are measuring: Use this base unit: Symbol of unit Mass Kilogram Kg Distance Meter m Time Seconds S Force Newton N The following prefixes in the SI system indicate the multiplication factor to be used with the basic unit. For example, the prefix kilo- is for a factor of 1,000. A kilometer is equal to 1,000 meters and a kilogram is equal to 1,000 grams. The more important SI prefixes in physics are: Prefix Symbol Meaning Multiplier mega M million 1x10 6 kilo k thousand 1x10 3 deci d tenth 1x10-1 centi c hundredth 1x10-2 milli m thousandth 1x10-3 micro millionth 1x10-6 nano n billionth 1x10-9 pico p trillionth 1x10-12 A pneumonic device can help you remember strings of terms. To remember the metric prefixes, you make up a silly sentence where the first letter of each word is a prefix, in order. For example, The Giant Man kept his dumb date coloring many unique neat pictures, or, The Great Monarch king had died one day cause my mother never prayed. Make your own pneumonic to remember the order of these prefixes: T G M k h d d c m n p 9 P age

10 Metric Conversion (subscripts represent the number of zeros in between the two prefixes) Y 3 Z 3 E 3 P 3 T 3 G 3 M 3 k 1 h 1 da 1 standard 1 d 1 c 1 m 3 3 n 3 p 3 f 3 a 3 z 3 y Gets smaller, moves decimal to the right, Gets bigger, moves decimal to the left, adds zeros LENGTH: 1. What is the basic unit for length? 2. Circle the best unit for measuring each distance: a. Thickness of an eyelash: mm cm m b. Length of a pencil: cm m km 3. Convert the following measurements: a. 34 mm = cm b. 3 km = m c. 234 cm = m d. 35 m = mm MASS: 4. What is the basic unit for mass? 5. Circle the best unit for measuring each mass: a. Amount of spices in a batch of cookies: mg g kg b. Your mass: mg g kg c. Mass of 10 pennies: mg g kg 6. Convert the following measurements: a. 16 mg = g b. 4.7 kg = g c. 12,345 g = kg d. 2 g = mg Compare using <, >, or =. 7) 63 cm 6 m 8) 5 g 508 mg 9) 1,500 ml 1.5 L 10) 536 cm 53.6 dm 11) 43 mg 5 g 12) 3.6 m 36 cm Write the correct abbreviation for each metric unit. 1) Kilogram 4) Milliliter 7) Kilometer 2) Meter 5) Millimeter 8) Centimeter 3) Gram 6) Liter 9) Milligram 10 P age

11 Try these conversions. Please show your work mg = g 2. 5 L = ml cm = mm km = m g = kg m = km cm = m ml = L g = mg kg = g Homework. Please show your work mg = g L = ml cm = m km = m g = kg m = km cm = m m = cm cm = m kg = g 11 P age

12 Study Guide List the steps of the scientific method. You wish to do an experiment to determine how a ball s radius affects how fast it rolls down a ramp. List the independent and dependent variables. Define: control variable and prediction. What is the difference between qualitative and quantitative measurements? What are the SI units used to measure: mass, time and distance? State whether you would measure each quantity in kilometers, centimeters or millimeters: the length of a car, a single grain of rice, the thickness of your math textbook, the distance from your house to school. What do the following SI prefixes mean: mm, cm, km, μm, Mm. Convert the following: 400 cm to meters, 50 grams to mg, 4 m to cm. 12 P age

13 MythBusters & the Scientific Method Directions: As you watch a Mythbusters episode, choose one myth to answer the following questions. Episode Title: Episode Date: 1. Explain the myth to be busted: 2. The MythBusters make a prediction at what the outcome is going to be for this myth. What is their hypothesis? What reason(s) do they give for their prediction? 3. What is your hypothesis? What reasons do you have for your hypothesis? 4. The MythBusters set up experiments to test the myth. Describe the variables and constants they used for their experiment. Independent Variable: Dependent Variable: Constants: 5. What was the control experiment? 13 P age

14 6. Explain the MythBusters procedure for testing the myth. Steps of the experiment: 7. Explain the results of the experiments. 8. What was the conclusion the MythBusters came to about the myth? 9. What specific data did they use to make their conclusion? 10. Do you agree with their conclusions? YES NO Explain why or why not by giving specific examples from the video. 14 P age

15 Mythbusters Project Guidelines Your project and poster are due on at the beginning of class. Your project and poster need to include all of the following components: Heading - A heading that clearly states the myth to be tested Prediction - Your guess about what will happen Experiment - A description of the experiment and the steps you followed Controls - What controls you used to show your data was worthwhile Data - The actual data you collected in table form Analysis - Your analysis of the results Conclusion - Was the myth busted? Your poster will be graded on your clear application of the above steps. Pay particular attention to the details of your experiment and your controls, they will be a major portion of the grade. In addition, creativity, neatness, design, and originality will count towards your grade. All of your data must be collected first in your lab notebook. I will be checking and grading notebooks as part of the project. The poster can be a summary of the experiment. If you would rather put less detail on the poster, then feel free to include additional typed pages that include details of the experiments, controls, or any part that you feel needs either more space or additional explanation. Be prepared to discuss your experiment and all of your results in class on. 15 P age

16 Mythbusters Worksheet 1. Explain the myth to be busted. 2. What do you predict will be the outcome of your mythbusting activity. 3. How do you plan to test the myth? 4. Describe the steps of the experiments 5. Describe what controls will you have in the experiment? 6. What kind of data will you collect during your experiment? 7. How do you think you will analyze and present your data (types of charts, graphs, pictures, etc.) 16 P age

17 Conceptual Physics Mythbuster Project Score Sheet 1. Project complete and on time (0-10 pts) 2. Poster is neat and well organized (0-10 pts) 3. Myth well explained (0-10 pts) 4. Experiment well defined (0-10 pts) 5. Experiments carefully completed (0-10 pts) 6. Data collected and documented (0-10 pts) 7. Controls explained and appropriate (0-10 pts) 8. Data analysis fits actual data (0-10 pts) 9. Conclusion is clear and appropriate (0-10 pts) 10. Presentation of project (0-10 pts) Total Points Comments: 17 P age