"Science Projects for kids
Rakesh Mohan Hallen
Make a Camera....................................................................................................................2 Make a Periscope.................................................................................................................4 Make a Telescope.................................................................................................................6 Make an Electroscope........................................................................................................10 Make a Sundial..................................................................................................................19 Make an Anemometer........................................................................................................23 Make a Hovercraft.............................................................................................................26 Make a Rocket...................................................................................................................28 Make a Water Wheel.........................................................................................................30 Make Bridges.....................................................................................................................33 Knot in a Bone...................................................................................................................35 Secret Messages.................................................................................................................37 Make Paper Airplanes........................................................................................................39 Make Sprouts.....................................................................................................................41 Make Dahi (Yogurt)...........................................................................................................44 Make Clouds in a Bottle....................................................................................................46
Make a Camera
Cameras have become a standard item in many households. You must have seen a camera somewhere, sometime. But do you know, what is a camera? What is inside it? How does it take photographs? Interested to know? Visit the following WebPages:
http://www.sederquist.com/clacamer.html http://www.cameracraft.com/camera.htm
But do you know, you can make a simple camera yourself. It is a bit difficult but definitely not very difficult. The most basic type of camera is the pinhole camera, which one can construct from a cigar box, aluminum foil, and sheet film. In this activity, we'll learn how to make a simple pinhole camera (we call it a pinhole scope) and how it works. A pinhole camera does not have a viewfinder; neither does it have any control of aperture or shutter time. One has to do them manually. But it cost so little. The major difficulty is in fixing the photographic paper/film and developing it. If you think your circumstances do not permit you to experiment with photographic paper or film, you can still see how the
image is formed in such a camera. A very simple description to make such a pinhole camera is provided at the following website, (don't be put off by the brand name of the container, understand and follow the spirit :
http://www.exploratorium.edu/science_explorer/pringles_pinhole.html http://acept.la.asu.edu/PiN/act/pinhole/pinhole.shtml
But, if you think you can handle photographic paper/film (it is not very difficult) then you will find the methods described in any of the following WebPages of great help. Visit all of them and decide which one is best suited to your taste and resources. All you need is a container for baby food or a paint, like the one shown in accompanying picture. You can easily get such a box from a scrap dealer (raddiwala), the rest of the requirements can be very easily arranged.
http://acept.la.asu.edu/PiN/rdg/camera/camera.shtml http://www.zeroimage.com/freeproject/oatmeal/oatmealcan.html http://users.rcn.com/stewoody/makecam.htm http://www.kodak.com/global/en/consumer/education/lessonPlans/pinholeCamera/pinhol eCanBox.shtml http://www.astro.wisc.edu/~mukluk/pin.html http://www.jankapoor.net/HexCamera.html
Make a Periscope
Are you familiar with the word "submarine"? A submarine is a kind of boat that moves underwater. Submarines are common crafts for the Naval forces of any country. But, while moving underwater, submarines need to know where they are with respect to other objects on the surface of water. The device they use to do this is called a periscope. Periscopes are optical instruments that can afford submariners a limited though vital visual picture outside their windowless hull. Traditionally, periscopes offered the submerged submarine its only glimpse of the outside world. Classic English war movies have also made them the submarine's most familiar feature. For most of us, who are unlikely to come across submarines in real life, a periscope can make it possible to see round corners and over the heads of crowds during processions or at sporting occasions. In a periscope, two mirrors are arranged at 45 degrees to each other. One mirror captures the rays of light from the object, and then they are passed down the tube to a second mirror which directs them into the eye. The use of two mirrors means that objects are viewed the right way round. Each mirror reverses the image and this results in a corrected image in the bottom mirror.
So, all you need to make a periscope is a long box or tube, and two mirrors. The long tube or box is rather easy to get or make. If you are ready to spend some money, you can easily buy PVC tubes from a hardware store. But, even when you are not ready to spend too much money, you can easily find such long boxes/tubes around you, for example you can use cardboard cartons on sherbet bottles, corrugated boxes used for supplying fluorescent tubes, you can use tubes used for tennis balls or shuttlecocks and so on, there are many options. The last but not the least viable option is to make such a tube your self. You can make it from a cardboard sheet, or from disposable paper containers used for cooking oils, fruit juices, milk etc.etc. Many people have described in detail, the method to construct a periscope, using any of the above options. Below is a list of addresses of such WebPages and that can help you according to your need and choice.
http://fog.ccsf.cc.ca.us/~tbardin/html/periscope.html http://www.pitara.com/activities/craft/online.asp?story=111 http://www.chariho.k12.ri.us/faculty/kkvre/units/light/periscope.htm http://www.nasa.gov/audience/foreducators/5-8/features/F_Construct_a_Periscope.html http://www.lightwave.soton.ac.uk/experiments/periscope/periscope.html http://www.exploratorium.edu/science_explorer/periscope.html
The more difficult part, as you may discover, is to get the two mirrors of the right size. Aluminum foils/sheets, or the reflecting surface of many disposable bags of food items can be perhaps used instead of the mirrors, but unless you are very lucky there reflectivity is seldom as good as that of a glass mirror. That's indeed the challenge for your innovative skills. Are you ready to take this challenge?
Make a Telescope
You must have heard about telescopes. If you are lucky you might have even seen one. A telescope is an instrument to view distant celestial objects, like the Moon, planets etc. Common telescope are called optical telescopes. They come in two varieties: refractors and reflectors. In refracting telescope (refractors), the optical system consists of lenses. Both the Objective (the optical system at the front end of the telescope) and the eyepiece (the optical system used to look through the telescope) are lenses. In the reflecting telescopes the objective is a parabolic mirror and the eyepiece is made of lenses.
The telescopes used by astronomers are often huge and cannot be constructed very easily. Often the most difficult job when a young enthusiast decides to make a telescope is to find lenses or mirrors. But we have found a design that is suitable for most young students in India. Parabolic mirrors for a reflecting telescope must be ground, which is rather arduous and time consuming. In this activity we shall make a reflecting telescope. Let us be first of all be familiar with its constraints. The magnification power of a reflecting telescope is equal to the ratio of the focal length of the objective lens to that of the eye piece. For example if
the focal length of the objective lens is equal to 100 cm and that of the eye pierce equal to 1 cm then we shall be able to see a distant object almost a hundred times bigger. The next constraint is the length of the telescope. A reflecting telescope will be at least as long as the focal length of its objective lens. Thus, the length of the telescope in the above example will be about a meter. We have chosen a design for this activity that would be practical to make under typical Indian conditions. You can acquire the lens for the objective of your telescope from an opticians shop (a shop from where one gets one's spectacles made). When you go to buy one ask him for a + .5 diopter lense with a diameter of about 5 cm. Should you fail to get a +0.5 diopter lense, take a +1 diopter lens. A magnifying glass ( a double convex lens) with focal length of 2 cm. or more can serve as the eye piece. You can take the help of your science teacher to get it. A lense of power 1 diopter has a focal length of 1 meter and a lense of power 0.5 diopter has a focal length 2 meters. Thus if we have a lens of power 1 diopter for the objective we shall need a tube at least 1 meter long. One can use PVC tubes normally available at a hardware store (a shop that sells sanitary ware, paints etc.) The tube that we can use for our telescope must have a diameter slighly larger then that of the lens. Since for a telescope we need to adjust the distance between the two lenses, we need two tubes. One longer for the objective lens and the other shorter for the eyepiece. The diameter of these tubes must be such that they can slide one over the another. In case, it is difficult to find such tubes, you can make your own tubes with the help of some thick paper and some adhesive tape or glue. The two lenses have to be secured firmly at the end of these tubes very firmly. You may use some bangles (choodiyan) for this purpose.
Once you have made up the telescope, you will find that it is very difficult to focus on any distant object, while holding it in you hand. So you will also need to improvise a method of clamping it to a firm object. Think, and improvise according to the conditions around you. You can find some useful tips on the following webPages.
http://www.ehow.com/how_17057_make-simple-telescope.html http://spikesworld.spike-jamie.com/science/astronomy/c421-01.html http://www.lightwave.soton.ac.uk/experiments/telescope/telescope.html http://home.houston.rr.com/molerat/tel.htm http://www.warren-wilson.edu/~physics/Contemp-Astronomy/Telescope/lenstel.htm http://www.funsci.com/fun3_en/tele/tele.htm http://www.ifa.hawaii.edu/users/mickey/ASTR110L_S04/simplescope.html http://www.exploratorium.edu/exploring/space/activity.html
Make a Stethoscope
A stethoscope is an instrument used by doctors to hear sounds generated from within human body. They are used to listen to the heart, lungs and intestinal tract. They are also used for measuring blood pressure. If you dream to be a doctor one day this activity will interest you a lot. You can make simple stethoscope very easily. But first of all you must learn a
bit about it. Visit the following website and you will find all the details about a stethoscope in a language that you can follow easily.
http://www.ahc.umn.edu/rar/MNAALAS/Steth.html
You may also be interested to know, when and who made the first stethoscope, and how its design has evolved ever since. The following website gives an exhaustive information about all this:
http://www.rossonhousemuseum.org/stethoscope_history.html
A stethoscope as you would now know, is based on the principle of collecting sound waves from a particular area, and transferring them to the ears of its user through a pipe/s. Thus to make a stethoscope you would need something to collect sound waves (like the bell of a doctor's stethoscope, and some tube. The most common object used for the bell of the stethoscope in the designs described in the following WebPages is a funnel:
http://www.scitech.org.au/body/circulatory_experiments.html http://www.schoolresult.com/experiments/science_experiments25.htm http://www.smm.org/heart/lessons/lesson4.htm
However, you can use any of the following if you cannot get hold of a funnel: An empty ice-cream cup A cover of a disposable soft drink tumbler The cover of a damaged electric plug top The cover of a boot polish container The next item you need is some PVC tube and a T joint.. You may get a t joint from a hardware shop or from a glass blower. You can get PVC tube from a doctor or a hospital (doctors often have to administer glucose or saline solution to their patients. These solutions are often dispensed in the
form of disposable polythene bags fitted with PVC tubes. If you can successfully collect all these items, you only need to use your ingenuity to put together a stethoscope. Do this activity in a group. Let everyone develop a design of stethoscpe oneself and then compare the results with those of others.
Make an Electroscope
An electroscope is a device that is used to demonstrate properties of static electricity. Static electricity is a phenomenon that takes many forms. It can be an electric shock you can get after walking over a carpet, or it can be a lightning bolt from the sky. The electroscope demonstrates the repulsive force that is exerted between two nearby objects with the same electric charge. In this activity you will learn to make your own electroscope. You won't need any exotic materials for this activity, all that is needed is readily available and can even be found in your house. First of all you must brush-up your knowledge about static electricity. The following links can help to a large extent; they have been listed according to their level of presentation:
http://home.att.net/~cat4a/static_electricity-II.htm http://www.amasci.com/emotor/stmiscon.html
To make an electroscope all you need is listed below: 1. An empty glass jar such as a jam jar. 2. A length of stiff copper wire about 12 cm long (or a large steel paper clip). 3. A sheet of aluminum kitchen foil about 20 cm square. 4. A strip of thin metal foil about 6cm x 0.5cm from a sweet wrapper. 5. A disc of cardboard about 10cm in diameter. 6. A small plug of M-seal putty. Make a very small hole in the centre of the cardboard disc. Bend over about 1.5cm of the copper wire at one end to make a right angle. Hold the other end of the copper wire between your fingers and thumb and push about one-third of its length through the hole in the cardboard disc. Secure this short length of the wire against the disc with adhesive putty like the M-seal. Roll-up the kitchen foil into a ball about 3cm in diameter and push it firmly onto the unbent end of the copper wire to a depth of about 1cm, taking care not to push the sharp end of wire into your hand. Fold the strip of sweet foil in half to make an inverted V-shape and carefully hook it over the bent end of the wire. Place the whole disc assembly on top of the glass jar with the aluminium ball above the jar and the hooked length of the wire inside of the jar. Ensure that the foil strip remains in place on the hook. You now have your completed electroscope. Now you would want to test it. All you need to test it is listed below: 1. A piece of silk the size of a handkerchief (or piece of cotton cloth). 2. A PVC plastic rod about 25cm long (or length of hard plastic material). Introduce a charge on the plastic rod by grasping it at one end and gently rubbing the far end with the piece of silk. Move the charged end of the rod near to the surface of the foil ball on the top of the electroscope, whilst closely watching the behavior of the inverted V-shaped metal strip on the wire hook within the jar. The ends of the strip should move further and further apart as the rod is moved closer and closer to the foil ball. An alternative to the charged plastic rod is a toy balloon. You can charge it up by brushing it against your hair. The electroscope works best on a dry day. On wet or humid days it might not work at all, because water vapour in the air continuously discharges the static charge that you are trying to create on the rod.
There are many other variations to this simple design. Do you want to explore them? It's very easy! just click on a link listed below and you will come across a new design.
http://pbskids.org/zoom/activities/sci/electroscope.html http://www.sciences.univnantes.fr/physique/perso/maussion/statelec/PagesEngl/Electrosc.html http://whyfiles.larc.nasa.gov/text/kids/D_Lab/activities/electroscope.html http://www.nfinity.com/~exile/electro.htm http://www.geocities.com/CapeCanaveral/Hall/1410/lab-GS-22.html http://www.rose-hulman.edu/~moloney/AppComp/2000Entries/Entry08/entry08.htm
These were the designs for the simplest electroscopes, known as metal leaf electroscopes. But these are still other variations, known as the electronic electroscopes. Would you be interested in making an electronic electrotrosope. You must first answer the following questions: Are you interested in electronics as a hobby? Have you seen and handled a soldering iron? Can you get/borrow a soldering iron? Do you know of a shop where you can get electronic components used in a radio transistor?
If your answer to all the above questions is yes, than only you can make an electronic electroscope. The design and instructions are presented on a webpage whose address is as follows:
http://www.eskimo.com/~billb/emotor/chargdet.html
Make an Electric Motor
Making a model of an electric motor is one of the most favorite project all around the world. Which is not particularly surprising considering the wide applications of motors in our daily life? As you have opened this page, it is evident that you are interested to make a motor. First all one must know how an electric motor works. The motion of an electric motor is due to magnets and electric current. You know the fundamental law of all magnets: Opposites attract and likes repel. So if you have two bar magnets with their ends marked "north" and "south," then the north end of one magnet will attract the south end of the other. On the other hand, the north end of one magnet will repel the north end of the other (and similarly, south will repel south). An electric current can also make a coil of wire magnetic. Inside an electric motor, these attracting and repelling forces create rotational motion. If you are interested to know more about the working of electric motors, visit any of the following WebPages.
http://www.howstuffworks.com/inside-motor.htm http://www.phys.unsw.edu.au/~jw/HSCmotors.html http://electronics.howstuffworks.com/motor.htm http://www.gizmohighway.com/howitworks/electric_motor.htm http://cipco.apogee.net/mnd/mfphowm.asp http://www.exploratorium.edu/snacks/motor_effect.html http://www.knowledgecontext.org/activities/connections/motor.htm
There are very many designs of electric motors that a young science enthusiast can follow. Many of such designs are available on the internet. Since the resources available to different people at different times can vary,
it is advisable that you study the various designs yourself and then decide which one is the best for you. Browse through the following links, each one of webpage that you can download through them tells you a design.
http://fly.hiwaay.net/~palmer/motor.html http://www.eec..."
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