Scientific Method
What is a control?
What is used for comparison in an experiment
What unit is used for temperature?
Celsius
350 dL ---> ? kL
0.0350 kL
1.2 X 10 ^3
1,200
What is matter?
Matter is anything that has mass and volume
Why do you need constants in an experiment?
You can only test 1 variable (the IV) and using more would make the experiment invalid
How do you find the volume of an irregular solid?
Water Displacement. You take an initial volume, next you place the object and get a final volume, and finally you subtract these numbers to the get the volume. I would be okay with giving units in mL or cm^3
15m --> ? cm
1,500 cm
332,000,000,000
3.32 X 10^11
What is the difference between mass and weight?
Mass is the amount of matter, whereas weight is the amount of gravity that is pulling on an object.
A student investigated whether ants dig more tunnels in the light or in the dark. She thought that ants used the filtered light that penetrated the upper layers of earth and would dig more tunnels during the daytime. Ten ant colonies were set up in commercial ant farms with the same number and type of ants per ant farm. The same amount of food was given to each colony, and the colonies were in the same temperature. Five of the colonies were exposed to normal room light and five were covered with black construction paper so they did not receive light. Every other day for three weeks the length of the tunnels was measured in millimeter using a string and a ruler. Averages for the light and dark groups for each measured were then computed.
What is the IV and DV?
IV: Amount of light (levels= light & Dark)
DV: Length of the tunnels in millimeters
What tools are used to measure the following:
Mass
Length
Temperature
Volume
Mass: Triple beam balance/scale
Length: Ruler or meter stick
Temperature: Thermometer
Volume: Graduated cylinder
230 mm ---> hm
0.00230 hm
0.00000305
3.05 X 10^-6
What causes a transition between the states of matter?
Temperature
A student investigated the effect of aged-grass compost (fertilizer made from decaying plant material) on the growth of bean plants. She thought that the compost would provide extra nutrients and make plants grow faster. Thirty bean seeds were divided into three groups and planted in different flats (boxes). All seeds germinated after 12 days and were allowed to grow for five days. The flats were ach given the same amount of water and the same amount of light. Flat A was then fertilized with 3-month old compost; Flat B was given 6-month old compost; and Flat C was given no compost. At the end of 14 days the height of each plant was measured in centimeters.
What was the control?
What were 2 constants?
Control: No compost
Constants: Same amount of light and water
What is the difference between weight and mass?
Mass is the amount of matter in an object (the "stuff) and weight is the amount of gravity that is pushing down on an object.
5 kg --> ? dg
50,000 dg
7.23 X 10^4
72,300
Solid: Definite shape & volume
Liquid: Definite volume & indefinite shape
Gas: Indefinite volume & shape
Dr. Smith wants to examine whether a new drug increases the maze running performance of older rats. Just like aging humans, older rats show signs of poorer memory for new things. Dr. Smith teaches two groups of older rats to find a piece of tasty rat chow in the maze. One group of rats is given the new drug while they are learning the maze. The second group is not given the drug. One week after having learned the maze he retests the rats and records how long it takes them to find the rat chow. Identify the IV, DV, 3 constants, and what type of graph would be used?
IV: If the rat was given the drug or not
DV: How long it takes the rats to go through the maze
Constants: Answers will vary- use your judgement (did it stay the same or should it)
Graph: Bar
What is the formula for density?
D= m/v
132mL--> ? daL
0.0132 daL
6.5 X 10^-5
0.000065
See board