What is a Good Question?

Transcription

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3 What is a Good Question?

4 1. A good scientific question is testable. Why is there air? What is the air made of?

5 2. A good scientific question can be tested with some experiment or measurement that you can do. Where did the universe come from? How fast does a football fly through the air when I throw it?

6 3. A good scientific question builds on what you already know. What chemicals are needed to make radishes grow? What is the source of genetic mutations in drosophila melanogaster?

7 4. A good scientific question, when answered, may lead to other questions. What is the colour of the sky? What events or conditions cause the sky to be blue (or orange or brown)?

8 5. A good scientific question is specific and not too broad. Why do leaves turn brown? Does the amount of water or sun a plant receives affect the colour of the leaf?

9 6. A good scientific question is related to the topic that is being researched. Why do leaves turn brown? Does the amount of water or sun a plant receives affect the colour of the leaf?

10 7. A good scientific question could have more than one answer, it is not a simple yes or no answer. Do plants grow in the dark? What lighting conditions are best for plants to grow?

11 8. A good scientific question is one that has scientific value. How is a planet s motion influenced by objects around it? When is my birthday?

12 Why do dogs bark? How are students grades affected by the amount of television watched? What temperatures cause bacteria to grow the fastest? What chemicals will prevent cut apples from turning brown?

13 Why are oceans salty? Is the bounciness of a basketball related to the temperature of the ball? Is protein synthesis affected when cells are placed in hypotonic solutions? What types of materials best reduce friction on a skateboard wheel?

14 Is the rate of hair growth affected by the amount of protein someone eats? Does baking soda and vinegar react? How often does the sun rise?

15 What is a HYPOTHESIS?

16 Is a possible explanation or a prediction for an observed causeeffect relationship. Is developed from the original question in the inquiry/investigation. Is based on prior knowledge.

17 The If or As part of the statement is the cause variable (independent variable) The then part of the statement is the effect variable (dependent variable)

18 Question: How does temperature (heat energy) affect the rate at which water boils? Hypothesis: If more heat energy is added to water, then the water will come to a boil faster because the water particles will be moving faster.

19 Question: How does the amount of time a student spends stuyding affect their grades? Hypothesis: If a student studies more, then their marks will improve because they have a better understanding of the material.

20 1. Why do people who smoke put more salt on their food? 2. How does the amount of sunlight affect the growth of a plant?

21 3. Why does water evaporate faster when its surface are is increased? 4. Why do plastic lids no longer fit their containers after going through the dishwasher?

22 What are VARIABLES?

23 use experiments to search for the cause and effect relationships in nature. design an experiment so that changes to one item cause something else to vary in a predictable way.

24 These changing quantities are called variables.

25 The cause or manipulated variable Values the experimenter chooses to change Plotted on the horizontal axis when graphing

26 The effect or responding variable Varies due to changes in the independent variable Plotted on the vertical axis when graphing

27 All other conditions kept the same Ensures a fair test

28 Question Independent variable Dependent variable Controlled variables How much water flows through a faucet at different openings? Faucet openings (closed, halfopen, fully open) Amount of water flowing in litres per minute Same faucet Same water presure Does heating a cup of water allow it to dissolve more sugar? Does an electric motor turn faster if you increase the voltage?

29 Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they re supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks. Problem: Smithers thinks that a special juice will increase productivity of workers. Specific question: Will the special juice that Smithers has increase the productivity of workers? Independent Variable Dependent Variable Controlled Variables

30 Homer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of treatment there is no change in the appearance of the green slime on either side of the shower. Problem: Homer s shower is covered in a strange green slime. Specific question: Will coconut juice remove the strange green slime that is covering Homer s shower? Independent Variable Dependent Variable Controlled Variables

31 Making Observations

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33 Contain a measurement of some kind Will have a number associated with it Examples: John has a mass of 70 kg The volume of the liquid is 250 ml.

34 Do NOT contain any numbers Are collected by your SENSES Examples: Susan has red hair. Bob is tall.

35 a. The concert was very loud b. The water was cold c. The reaction took 48 seconds to occur d. The grass was green e. The volume of the object was 4.9 L f. The length of the trip was675 km g. The sandpaper was rough. h. The sugar plus sulfuric acid turned black, then grew to the height of 20 cm.

36 Recording Results and Observations

37 Question: How does the amount of water consumed in a day affect the number of times you pee? Table 1. Effect of the amount of water consumed on the number of times you pee. Day Amount of water (ml) Number of times peed (/day)

38 Question: How does the amount of stirring affect the amount of salt that dissolves in a glass of water?