Variables
Scientific Method
Vocabulary
All about Density
Calculating Density
100
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 Krabby patties with the new sauce. The other 50 (Group B) eat Krabby 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. What is the independent variable?
The special sauce (ingredient)
100
Write a hypothesis using the formula. How does classroom temperature affect student performance on a test?
If the classroom temperature is above 80 degrees, student test performance will decrease. ETC.
100
Define "mass".
The amount of matter or "stuff" in an object.
100
Why do you float better in salt water than freshwater? Explain
Salt water is more dense than fresh water.
100
Find the density of the object below. Mass=32g Volume=17cm3
1.88 g/cm3
200
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. What is the dependent variable?
The scent of Gary's shell
200
Write a hypothesis using our formula. How does fertilizer affect plant growth?
If you add fertilizer, it will increase plant growth.
200
Define volume.
The amount of space an object takes up.
200
What is the formula for density?
Mass/volume=density
200
The mass of a toy spoon is 7.5 grams, and its volume is 3.2 ml. What is the density of the toy spoon?
2.34 g/ml OR 2.34 g/cm3
300
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. What is the dependent variable?
The dependent variable is the amount of gas.
300
A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. The dependent variable is the ____. A. diameter of the ball B. force acting on the ball C. height that the ball bounces D. height from which the ball is dropped
C. Height that the ball bounces
300
Define "density".
The amount of matter compacted into a given space.
300
Why does changing the shape of an object have no effect on the density of that object?
Density does not change no matter how large or small the amount of an object is. Density of water is always 1g/ml. The same amount of atoms are still packed within a set space.
300
A chef fills a 50 mL container with 43.5 g of cooking oil. What is the density of the oil?
0.87 g/mL
400
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. What is the independent variable?
The independent variable is the use of seaweed.
400
A student hypothesized that the amount of sunlight a sunflower plant receives determines the number of sunflower seeds the plant produces. In her experiment, the number of seeds produces is the _____. A. dependent variable B. independent variable C. controlled variable D. manipulated variable
A. Dependent Variable
400
How do you find "water displacement"?
Fill an graduated cylinder to a set volume. Record it. Add the irregular shaped object. Record the volume of the water level now. Note the difference. Final Volume-Original Volume=Volume of the irregular object
400
Which of the following materials will float on water (density 1 g/ml)? corn oil =0.93 g/cm glycerine =1.26 g/cm3 corn syrup = 1.38 g/cm3 wood =0.85 g/cm3 steel = 7.81 g/cm3
Wood & corn oil would float.
400
Your have a box that has a volume of 412 cm3 and weighs 42g. What is its density?
0.1019 g/cm3
500
Four groups of rats are first massed and then fed identical diets except for the amount of vitamin A they receive. Each group gets a different amount. After 3 weeks on the diet, the rats’ masses are measured again to see if there has been a decrease. What is the independent variable? Dependent Variable? And the control?
IV: Vitamin A DV: Mass of the rat CV: Identical Diet
500
scientist plants two rows of corn for experimentation. She puts fertilizer on row 1 but does not put fertilizer on row 2. Both rows receive the same amount of water and light intensity. She checks the growth of the corn over the course of 5 months. What is a controlled variable in this experiment. A. Amount of water B. Corn without fertilizer C. Corn with fertilizer D. Plant height
A. Amount of Water
500
What is a meniscus?
The curve created by the attraction of liquid molecules to the side of a liquid container
500
Mercury has a density of 13.53 g/cm3. You drop an object into the mercury that has a density of 18.88 g/cm3. What will happen to the object?
The object will sink because it is more dense than mercury.
500
A cube made of very old hard wood, has a mass of 45g and measures 6 a side. Tell me its density AND whether in will sink or float in a bucket of water. (REMEMBER water's density is 1g/mL)
(Volume 6x6x6=216) 1. Density=0.208 g/cm3 2. The cube will float in water because the cube (0.208g/cm3) is less dense than water (1g/mL).
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