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The Scientific Method

Are you doing science activities or science experiments?  Do you know it isn’t that difficult to turn an activity into an experiment?  An activity leaves out the critical thinking process that is so well formulated in the scientific method.  Use these age-adjusted steps in the scientific method to help you with your science studies by transforming your activities into experiments!

For Your Youngest Child
These questions should be asked orally.  Introduce as much vocabulary and terminology as your child has the attention span for.

What do you think will happen?
What happened?
Draw a picture of what happened and label it (with help)

For Elementary Students
These questions should be asked orally with the answers to the questions dictated by the student and recorded by the parent onto the experiment writeup or observation sheet.  If your student can write, then he should do the writing himself.  Introduce as much vocabulary and terminology as your child has the attention span for.
 
What do we want to find out?
What do you think (or guess, or hypothesize) will happen?
What do we need in order to find out the answer?
How will we test our guess (or hypothesis)?
What happened? (Use a simple chart or graph as appropriate to record results)
Draw a picture of what happened and label it.
What do you conclude from this experiment?

For High School Students
The college preparatory high school student should be using all the steps in the scientific method and producing a typed or handwritten report for his or her science notebook.  The italicized steps below require more effort and are typically reserved for a science fair project or professionally published report.
 
Statement of the Problem
Research of the Literature on the Topic
Hypothesis
Materials List
Procedure Used
Observations
Calculations
Results
Statistical Analysis
Sources of Error
Conclusions
Possibilities for Future Research

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Aerodynamics Experiments to Share With Your Kids

By Aurora Lipper

This article teaches kids about aeronautics and gives a handful of totally fun activities to experiment with for their homeschool science learning (including helicopters, parachutes, and other flying machines).  It’s also good for boy scouts working on a badge, or for any kids that love science experiments.  These experiments are part of a homeschool science program that I teach, and I promise your kids will love it.

Every flying thing, whether it’s an airplane, spacecraft, soccer ball, or flying kid, experiences four aerodynamic primary forces: lift, weight, thrust and drag. An airplane uses a propeller or jet engine to generate thrust. The wings to create lift.

The smooth, pencil-thin shape minimizes drag. And the molecules that make up the airplane attributes to the weight.

Let’s find out what are all the parts of an airplane for. You’ll need to get a cheap balsa wood airplane for this next part – check out your local drug store or toy store. I’ve even found them in grocery stores for about $2.

Take the balsa wood airplane and try to fly just the body (no wings or fins). It flips all over the place. Try flying just the large wing (no body). Somersaults! Now slide the large wing into the body and fly (fewer somersaults, but still sickening to fly in!). Now add a horizontal stabilizer (elevator) tail, and when you throw it, add a slight curve so the plane “fishtails” in the air (like a car)… but did you notice that there are no more somersaults? Add the vertical tail (rudder) and see how it now steers straight no matter how to curve-throw it.

Sneaky Tip: if you remove the metal clip on the nose beforehand, you can add it last to really see what it’s for… notice where most of the weight is without the clip?

Tip for Teaching Homeschool Science:  Keep a small box handy with these items inside: paper clips (in two different sizes), rubber bands, scotch tape, scissors, index cards, string, copy paper, hole punch, crayons, and a stapler.  Label your box “Flying Paper Machine Equipment”.  Pull the box out, add kids, and stand back.

Ready to make more flying things?  Let’s make more things that fly, zoom, twirl, and soar while teaching homeschool science at the same time!

Helicopters. Cut out a paper rectangle 5 by 2 inches. Cut lengthwise down the strip, stopping about an inch before the end. Tape this uncut inch to the end tip of a popsicle stick. Fold the “bunny-ear” flaps down in opposite directions. Throw off a balcony and watch it whirl and gyrate! Optional: You can notch the end of the popsicle stick to make a sling-shot helicopter. Make a quick slingshot launcher by looping a rubber band to another popsicle stick end.

Butterfly Cups. Tape two Dixie paper cups together, bottom-to-bottom. Chain together six rubber bands. Loop one end of the rubber band chain over your thumb and hold your arm out horizontally straight, palm up.  Drape the remainder of the chain along your arm. Place the taped butterfly cups at the free end (near your shoulder) and slowly wind the rubber bands around the middle section of the cups. When you wind near the end, stop, stretch the chain back toward your elbow, make sure the rubber band comes from the underside of the cups and release. The cups should rotate quickly and take air, then gracefully descend down for a light landing. Try making one with four cups.

Hot Air Balloons. Shake out a garbage bag to its maximum capacity. Tape (use duct or masking tape) the open end almost-closed… you still want a small hole the size of the hair dryer nozzle. Use the hair dryer to inflate the bag and heat the air inside (make sure you don’t melt the bag). When the air is at its warmest, release your hold on the bag while you switch off the hair dryer. It should float up to the ceiling and stay there for a while. This experiment works best on cold mornings. The greater the temperature difference between the bag’s air and the surrounding air, the longer it will float.

Parachutes. Attach a piece of floss or thin string to the four corners of a tissue. Attach a stick, a small wad of stones wrapped in another tissue, a pinecone, etc. to the centers of the string. Practice dropping these from the balcony and see which falls slowest with which load.

Ring Thing. Cut an index card into thirds lengthwise. Loop one strip into a circle and tape ends together. Place two remaining strips together end-to-end and tape, then loop into large circle and tape in place. Place a piece of tape across one end of a straw and gently secure one ring to the tape. Repeat on the other end with remaining ring. Make sure the two rings are concentric (you can see through both like a telescope). Throw it small-end-first!

Free Form Machines. Make an obstacle course with some or all the following different challenges: Hit a target balloon (arm the machines with opened paper clips); Go over and under a suspended length of string; Make it through a hula hoop suspended vertically or horizontally; Carry a jelly bean passenger safely across shark-infested waters (two tables spread apart); Dangle large paper airplanes (made from 11×17″ paper, or two 8.5×11″ papers taped together to make an 11×17″) from the ceiling for a ‘dogfight’ to earn points if you tag one; Shoot through the basketball hoop, and dive into a basket.

Article Source: http://www.articlesbase.com/homeschooling-articles/aerodynamics-experiments-to-share-with-your-kids-359924.html

About the Author:  As a teacher, homeschool science teacher, engineer and university instructor Aurora Lipper has been helping kids learn science for over a decade.

Editor’s Note:  Some of the experiments mentioned in this article are actually activities.  To turn an activity into an experiment, be sure to incorporate the scientific method by making a hypothesis about what will happen, conducting the experiment, recording the results, analyzing the results, drawing a conclusion, and, for older children, making a report.

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Activity: Experiencing Centrifugal Force

To perform this activity, you will need a merry-go-round and a small, light-weight ball.

1.  Get onto the merry-go-round and hold on tight.  Have someone spin you very fast. 
    a)  How do you feel yourself being pulled? 
    b)  If you were to let go– which you certainly won’t do– which way do you think you would go? 
    c)  Try moving to the center of the merry-go-round, to a point mid-way between the center and the edge, and then the edge.  At which location do you experience the most “pull”?

2.  Now have the person spin you at a moderate rate while you hold the small ball. 

3.  Look for a landmark object, such as a tree.  The next time you come to the tree, let go of the ball.  Make sure you just let go, don’t throw it.     
    a)  Where does the ball end up? 
    b)  Did it go directly towards the tree?

Have you ever been on one of those amusement park rides that you stand up in while it spins around very fast?  If you have, it feels as if you are being thrown out against the side doesn’t it? 

It’s called centrifugal force, but it is not a force at all.  It is an effect you feel that results from the curved shape of the ride and the forward motion you have.  An object moving in a circle, acts as if it were experiencing an external force when in fact it is not.  Centrifugal force is dependent on the the object’s mass, rotation speed, and the distance from the center of rotation. 

If the walls of the amusement park ride were to suddenly disappear, which way would you go– straight back, or to the side?  Remember which way the ball went when you let go of it while spinning around.

Think of what happens to you when you are in a car that turns suddenly.  You are thrown up against the side of the car.  The reason is explained by understanding an insight from Galileo.  He said things like to keep going the same direction and the same speed.  It takes a force to change the direction or speed of something.  So when the car turns, your body wants to go straight, at least until it is pulled back by the seat belt or hits the side of the car!  Thus, it feels as if you are being thrown up against the side of the car, when in reality you are just going straight as before, while the car is turning.  To better understand this, imagine that the amusement park ride is a square box instead of a circle.   What would happen?  You can try it with a marble and a cardboard box.  Spin the box with the marble in it and watch what happens!