EGG EXPERIMENTS
Vocabulary
Variables are characteristics or conditions that exist in different amounts or types and can be changed in an experiment. There are three types of variables: independent, dependent, and controlled
It is a variable that stands alone and isn't changed by the other variables you are trying to measure. Example: amount of fertilizer given.
The variable that is made to change. Example: growth of a plant (affect).
A control variable is the thing in an experiment that is unchanged and constant. The independent variable is the variable that is changed on purpose to test the dependent variable.
An easy way to remember is to insert the names of the two variables you are using in this sentence in they way that makes the most sense. Then you can figure out which is the independent variable and which is the dependent variable:
(Independent variable) causes a change in (Dependent Variable) and it isn't possible that (Dependent Variable) could cause a change in (Independent Variable).
For example:
(Time Spent Studying) causes a change in (Test Score) and it isn't possible that (Test Score) could cause a change in (Time Spent Studying).
We see that "Time Spent Studying" must be the independent variable and "Test Score" must be the dependent variable because the sentence doesn't make sense the other way around.
Let's Play with Eggs!!!
Make an egg bounce!
Two cups, vinegar, corn syrup (3 days)
Place a raw egg into a jar and cover with vinegar. Leave egg in vinegar for 2-3 days or until shell is completely dissolved. Rinse egg in water. Gently drop egg on floor or counter from about 1 foot in the air and watch it bounce! It will break eventually and from a higher dropping point.
Examine the egg.
Look at shell from the boiled egg. Identify the air sac at end of one shell. The air sac helps cushion the chick while it develops.
Also identify the egg membrane on the shell. The membrane is another protective barrier for the chick and also helps get the air (that comes from the pores in the shell) to the chick while it is developing.
After looking at the raw egg and identifying the parts, take a toothpick and break the membrane around the yolk. Gently poke the yolk, which will pierce the membrane. The yolk will ooze out! (Note: The membrane around the yolk is not the same membrane that is seen inside the shell)
Humpty Dumpty Experiment
Materials: Boiled eggs, Ziploc bags, independent variables (cotton wool, cous cous, rice, bubble wrap)
Think About:
What control variables do you need to keep constant to make the experiment as accurate as possible?
VARIABLES TO KEEP CONSTANT
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Height to drop the egg
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Force at which to drop the egg – we used the same person to hold the bag as high as they could and then drop it without using any added force. This meant the height and force should be the same for each egg.
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Amount of material to test – this is a tricky one. We drew a line on the bag and filled it to the same height with each material; there are some issues with this, as the bubble wrap had more air gaps than the other two materials.
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Placement of the egg – if the egg was on the bottom of the bag, it wouldn’t be cushioned, so we tried to make sure the egg was in the middle of the material we were testing.
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The surface on which to drop the egg – this should be the same
HUMPTY’S EGG DROP INSTRUCTIONS
Place your material to test in a sealable plastic bag, add the egg and make sure it’s completely covered by the test material.
Egg Lander Design Challenge
Design a landing craft that protects your egg passenger when it's dropped from up high. Use the engineering design cycle for this experiment: design your landing craft, test it to see if it works, change your design to make it better, and re-test to get new results.
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Collect your materials. You’ll need a container, some internal padding and external protection to safely land your craft. There's no "right" set of materials, so be creative and try lots of things to see what works best!
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Draw your design ideas on paper. What does your lander look like? What materials will you use? Try using just one container, one type of internal padding and one type of external padding at first.
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Build your landing device and put your egg inside. Test it out by dropping your device from up high. If the egg doesn’t crack, your design is a success! If the egg cracks, make changes to your design and re-test it.
What's happening?
Gravity is a force of attraction — it pulls on a mass, which is how much “stuff” something is made. Earth’s gravity pulls on you and keeps you on the ground; it also holds the atmosphere and the moon in place. When you drop your landing craft, gravity pulls it to the ground.
The internal padding that surrounds your egg cushions the payload inside the container, like airbags in a car that protect passengers in an accident. The external protection on the outside of the container protects the egg by absorbing the impact felt when the landing craft hits the ground.