Take a 2 liter bottle and fill it with water up to 2/3 level. In the kit, there is a small plastic bottle, with a cap. This is a 'Cartesian diver'. In 2 liter plastic bottle filled with water, gently drop this Cartesian diver upside down. Cap the plastic bottle tightly. You will find that the Cartesian diver will sink a little bit and remain just below upper level of the water. Press the bottle gently and notice a miracle. The Cartesian diver dives deep into the water and touches bottom of the bottle. As
you release the bottle, it bounces back to its original position. You can repeat this fun exercise till you understand science behind this miracle.
How does it happen?
The Cartesian diver has a cap with a central tube. Initially, the diver is in the top layer of water. The diver is filled with air. We know that air also has some weight. Being it is lighter than water, the diver rests in the top layer. When we press the bottle, air in the plastic bottle is compressed. It exerts pressure on water in the bottle. Water enters the diver making the diver heavier. So the diver sinks .As you release pressure from the plastic bottle, the water from diver comes out and it becomes lighter. So it bounces back to its original position. It is a classic experiment in properties of air. It is named after the scientist, Rene De-cartes (1596-1650). We learn that air has weight, it exerts pressure and it can be compressed. This diver is also useful in understanding concept of buoyancy and even Archimedes principle.
1.]Punch the color disk carefully out of the cardboard sheet. Put the disk onto the top
2.] Now spin the top as fast as you can. ask your parents for helping in spinning the top. When spinning, the different color can no longer be distinguished. They can no longer be distinguished. They merge into a gray, almost white color.
White is a mixture of all colors even though it may not seem so to us. One could also say that all colors are contained in white light. This is why white can be composed of the different colors. And that is exactly what you do with the color
wheel. It is really your eyes that are observing the change in color because they cannot follow the fast-spinning top,
rather than the object actually changing color itself.
Take other tube from the kit which has two small holes in the center. Also find two long plastic tubes. They have small holes drilled at one end. Insert these tubes into two holes of the fountain tube with their ends with holes going into the tube. Do not insert it up to the holes. Just insert the tubes by 10 mm or so. Take two plastic bottles (soft drink or mineral water) and fill one 3/4 full with clear or colored water. Remove cap of the bottles. Also remove plastic sealing rings. Screw the fountain tube with two plastic tubes on to this bottle.Cap other bottle oh the other end of the fountain tube. Just turn the bottles over and a bubbling, spurting fountain will occur at the top of the plastic tube. Turn it over when the upper bottle is empty and the fountain occurs again. You don't have to shake the bottles. How does it happen?
Closely observe what happens.. When the bottle sare inverted, gravity pulls the water from the upper bottle down through the lower tube and compresses the air in the lower bottle. When water leaves the upper bottle, a partial vacuum or decrease in the pressure occurs in the upper bottle. Air is then forced from the lower bottle to the upper one through the fountain tube. The long tube which we have inserted, has small holes at one end. This end is at the bottom of the upper bottle. The air that comes up from lower bottle also takes along water from upper bottle coming into tube through small holes resulting into a bubbling fountain. Try following things to demonstrate two actions occurring at once, viz, formation of partial vacuum in upper bottle and compression of air in the lower bottle : a.) Start the fountain and then unscrew the lower bottle. Lift the fountain as shown. Air rushes from outside through the tube to occupy the empty space (partial vacuum) and takes water with it, resulting into a fountain. That means there was partial vacuum in the upper bottle as discussed earlier. b.) Cut the base off upper bottle. Close hole of the fountain tube through which water enters into lower bottle with your finger.Fill the upperbottle with water and now remove your finger from the hole. As water starts entering the lower bottle, fountain starts. Here, the vacuum is not created in upper bottle as the bottle is open, but air in the lower bottle is compressed and pushed upward,resulting into a fountain.
Pyramids have long been a thing of mystery since their origin sare clouded in the mysteries of the ancient world. So it is not surprising that somebody would invent puzzles based upon a pyramid shape. This Web page concerns three-dimensional puzzles that form a pyramid shape. (See also the Tower Puzzles in the puzzle section, which some authors also classify as Pyramid Puzzles.)
This is a "simple" two piece puzzle. It's been around for a long time - the creator is unknown. The Museum's copy was purchased in 1972 from World Wide Games, Delaware, Ohio. When put together correctly the two pieces form a three sided equilateral pyramid.In geometric terms this pyramid is really a tetrahedron (a figure with four equal sides). Although the pyramid has three visible sides which form the point at the top, the base forms the fourth side. The tetrahedron has been cut in half to form two identical pieces as shown in the photo at the left.
The solution to the puzzle is in the photo at the right. Note that the square areas of each of the 9.5cm pieces are placed facing each other, and one piece is twisted upright - thus the pyramid is formed.
This is an interesting toy, with a unique feature. Apparently it looks like a spherical shaped top with central stem. You will realize its beauty only when you spin it. Hold its stem in thumb and middle finger. Roll the stem sharply through the fingers and drop the top on a flat surface. As expected, the top starts spinning on its spherical surface. The surprise is that the top spins on its spherical end for only a few seconds and then, unexpectedly, turns upside down and spins on its stem.
How does it happen? Apparently, inversion of the top looks like violation of the law of the "Conservation of Energy" because the top seems to raise its centre of mass without outside help. In the case of this top, its centre of mass or centre of gravity is in the spherical section of the top. How can the top turn upside down and spin on its stem? Eminent scientists, like, Neils-Bohr and Lord Kelvin have spent their time playing with this toy to explainmechanics of this top. The top has a fascination, that it surprises all, irrespective of age and profession.
Let us understand what makes it turn up-side-down ? The reason is quite simple. As we spin the top, there is friction between the top and the surface. It creates sliding frictional force in the direction along the flat smooth surface. As a result of this sliding frictional force, a torque is created about the centre of mass of the top. This torque gives the top necessary momentum to invert. If you add a little weight by adding a drop or two of wax inside of the spherical section or on the upper surface of the top, the result will be different. Just try it out.
There is a top in the kit, which looks more like a boat, than a top. It has one flat surface and the other one is curved. Keep the top on its curved surface. Use glass or any other smooth surface. Gently spin it in clockwise direction. The jerk should be so gentle, that it takes just 4-5turns.
See what happens?
The top takes 4-5 turns as expected and suddenly, something unexpected happens. It rocks up and down for a while and starts spinning in anti-clock wise direction. Try to spin it in anti-clockwise direction. You
will find that the top keeps spinning till frictional force stops it. That means, the top has some special favors for one direction. It prefers spinning anticlockwise.
Try one more thing. Just tap on one end of the top gently. See what happens. The top automatically starts spinning in anti-clockwise direction.
How do we explain this miraculous behavior of the top? Let us find out...
How does it happen?
Mysterious behavior of this top is quite difficult to explain. These kinds of stones were known in nineteenth century and they were called as celts. Scientists of that time tried to give scientific explanation of this miraculous reversal. In the recent past, physicists have worked on this mystery; however, its mathematics is yet to be understood completely. The physics of these tops can be explained as under: The top has smooth ellipsoidal bottom. In any normal shape of this type, the ellipsoidal base should have been aligned to its top surface. In case of this top, it is not true. That means, the point on which the top rests is not the centre of this body, but is shifted. This misalignment of the ellipsoid from the principal axis is one important reason for reversal. In addition to this, mass distribution of this top is not uniform for the two principal axes. The function giving the distribution of mass with respect to a particular axis is called the moment of inertia. That means, the moment of inertia is different in two axes in the case of this top. Besides, two axes of the ellipsoid have different radius of curvature. To sum up, we may say, the mass distribution along two principal axes and their moment of inertia are uneven, centre of this top is shifted and radius of curvature of the two ends of the top is different. These reasons attribute to the reversal of this top.
a.] Carefully break the sundial disk loose from the printed Assemble the sundial by pressing the obelisk through the disk from the back.
b.] On a sunny day wait until the clock is at a full hour and place sundial in the sun. If, for example, It is 12 noon, turn the sundial so that shadow of the obelisk points directly at the number 12 on the sundial disk. the sundial is set, and from now on you can read the time on your sundial
How does it happen?
Because the earth turn sa round it sax is,it appear to us as if the sun turn sa round the Earth.The shadow cast by the obelisk will therefore wander on the sundial. It is the hand of the sundial. But the sundial only works in nice weather and only from morning until night. Also don`t forget that in the spring and summer we have daylight saving time. In the summer when your watch shows 12, the time according to the position of the sun is only 11 o`clock.
You will find two identical tubes in kit. out of which, one is to produce a "Tornado" in a bottle. Pick up one, which has One hole in the center. Take two clear and empty soft drink plastic bottles. Ensure that tornado tube can be screwed onto them tightly. You must remove plastic sealing rings from both the bottles, before you fit tornado tube. Fill one bottle with water up to 2/3 level. You may add very small quantity of color if you wish. However, to begin with, it is better to do with clear water. Screw second bottle on the other side of tornado tube. Tighten it fully. The assembly would look like one shown in the figure. Turn the bottles upside down. This will take the filled bottle on the top. Shake the upper bottle, giving swirling motion to the water inside the bottle. Observe carefully, the spinning water creates something in the water that looks like a Tornado! The water will keep coming down into the empty bottle and in the middle of the upper bottle; this tornado effect will be visible. Once upper bottle is empty,you may turn them up-side-down and repeat the actions to
see the torn adoeff ectaga in.It is a Vortex.…The swirling tornado in the bottle is referred to as a vortex, which is a type of motion that causes liquids and gases to travel in spirals around a centre line. During summer days, we often find gusty winds producing miniature tornadoes called dust devils. Such dust devils have similar shape like a vortex. In rivers, there are similar vortices seen during floodconditions. How does a vortex occur in a bottle? A vortex is created when rotating liquid falls through an opening. The liquid is pulled by gravity into the hole. Water from the upper bottle has developed rotating action. As some water enters the hole air from lower bottle rushes to the upper bottle. Due to rotating action of liquid, there is a centrifugal force acting on it, so the air can come up through the centre more rapidly. Due to this a vortexis developed in the centre ,resembling to a tornado.
Try this ... You may try many new things with your tornado tube, here are a few suggestions. Think and do your own experimentation: a.] Compare the speed of water flowing from upper bottle to lower bottle with and withoutshaking the bottles.That means, once water comingdown on its own and next time it is coming down in a swirling action forming a vortex. b.] Add some plastic shapes, like animals, trees, small house etc. in the bottlebefore forming a tornado. See how are they displacedwhen tornado actionstarts. This may remind you of real wild tornadoes which lift dirt, trees, animals and houses into the air by the swirling vortex. c.] Fill water in two bottles with 2 separate colors, like yellow and red or red and blue. Quickly connect them to the tornado tube and see which color develops when water comes down and mixes in the water with other color. d.] Try to form tornadoes using other liquids, like, cooking oil, kerosene and evencombination of water and any of these liquids. e.] Add some silver or golden glitter in the water before forming a tornado. You may use kerosene. in this experiment mixed with water to improveits performance. Besides, you may invent your own tricks and demonstrate more interesting activities with the tornado tube. Never forget that it is fun to find out new things ratherthan just doing what is asked for.
In the kit, there are two disks with holes. These are the spinners, which produce his sing sound as you spin them rapidly. Let us do this first. Take one disk and make a loop of thread given in the kit while passing the thread through two small holes in the
centre of the disk. The loop should be of optimum length, so take thread of approximately 100 cm. length. Spin the spinner rapidly as shown in the figure. Once it gets enough spin,it starts producing hissing or whistling sound. You may repeat this experiment with another disk. It will also produce similar sound. Keen observation will reveal that there is some difference in the sound produced by two disks. Let us know the science behind spinners.
How does it happen?
Let us first know, what is 'Sound'? Sound is a form of energy produced by something vibrating. Or we can say that vibrating energy is converted into sound energy. Sometimes we can see these vibrations, while most of the times we cannot.If we pluck a tightly held elastic band, it shows vibrations, while it produces sound. However, when we speak, sound is heard but vibrations are not seen. When we speak, we set air molecules around us vibrating. Air acts as a medium and carries these vibrations or sound waves to our ears. Look at the disks that you are spinning. They have a few holes near their periphery. As we spin them rapidly, air passes through these holes and vibrations are set in. These vibrations produce sound which is audible to human ears. Even when we spin the disks slow, vibrations are created, but sound produced by these vibrations is not audible to human ears. If we notice carefully, the disk with small holes produces sound with higher pitch. You must know that the technique of producing sound by passing air through holes is used in factory sirens.
11. Hover Craft There is a circular disk with central stem and a small plastic tube in the kit. This is
the Hover Craft. Place a balloon on the rim of plastic tube. Inflate it by blowing air through the tube. Once the balloon is inflated, hold it tight in your fingers just above the tube to prevent air from spilling.Place the tube with balloon on central stem of hover craft. Keep the hover craft on glass surface or smooth laminated dining table. See what happens.. The hover craft starts moving on its own. It keeps moving until the balloon runs out of air. Remove the balloon with the cap and inflate it again to repeat the action.
How does it happen?
The disk has a small pin-hole in the centre. As the inflated balloon is fixed onto it, the air starts coming out from the pinhole.The air is distributed evenly under the disk and a small film of air is created underneath. This reduces friction between the disk and glass surface. The disk starts moving freely on the surface. Same principle is used in real Hover Crafts or Air Cushion Vehicles. These vehicles have large fans which create air cushion under the vehicle and it is lifted above the surface (usually sea surface). Such vehicles can travel at incredible speed as their friction is minimized. Hovercraft can be termedas aero plane flying without wings or ship sailing without sails. As it moves on the layer of the air, it can move on both the surfaces-land and water.
You will find a few metal shapes & a top with magnetic tip. Spin the top just near these metal shapes & see the fun. The metal snake starts moving back & forth with the top. The top has ferrite magnet fitted just above the revolving tip. Due to magnetic induction the steel rivet on which the top revolves also behaves like a magnet & holds the metal shapes.
The flick disk is a great outdoor toy for we all to enjoy and learn a bit more about aerodynamics and energy. Fly the disk on the ground, where there are no trees. You may lose the disk if you try it near trees. Also make it sure that the disk does not hit other persons.
How to fly?
1. Hold the disk in your right hand. The disk has a notch on its periphery.
2. Hold rubber band in your left arm. Lock its one end into the notch of the disk.
3. Stretch the rubber as much as it can allow you to stretch.
4. Hold the disk in horizontal position before you release it. Now once you are ready, release the disk from your right hand. Make it sure that your grip on rubber band by left hand is still firm or else rubber band will also be released.
5. The disk flie soff with great speed. It rotates and glides for a very long distance.
How does it work?
The first action of releasing the disk is an application of potential energy of stretched rubber band. When we stretch rubber band, the energy is in potential form. It becomes kinetic, the moment we release the disk. The disk flies horizontally, due to its rotation. Rotating disk creates an angular moment perpendicular to the horizontal plane. It stabilizes the disk in high speed flight. If released well, it can fly in a straight line. It covers vary long distance due to its thin profile and round edges.Try to give a little angle to the disk while releasing it. Rim of the disk has a airfoil design. It can take a flight and can also come back to you on completing a circular path.
14. DISK IN MOTION Make the spinningtop spin by quickly moving your fingers.Now you can carry out various experiments Experiment A.] “colour -mixing”disk: While the spinning top is spinningcolors which are not on the disk appear. Why?
The images of the colors in motion remain in the eyes which transmits them to the brain in a mixture of colors. When the disk is still all the colors are transmitted to the brainone-by-one B.] “Color-creating” disk: Shades of variouscolors appear near the black lines. Why?
While the disk is in motion the eye receive flashes of black and white which produce the effect in the brain of seeing colors. C.] “magic” disk: If you carefully watch the spinning top while it is spinning and lit up by a light, at a certain point the sections of the disc create the perception that the spinning top shows down, then stops for a second and then it spins in the opposite direction. Why? Domestic light flash extremely quickly (faster than the human eye can see) and this create the impression of seeing the disc come to rest and the illusion that it then spins in the opposite direction. (By the light of the Sun or when using a torch this phenomenon does nothappen).
15.Balancing Question You must have noticed a question mark shape in the kit, and perhaps puzzled with the kind of toy it is. Let us play with it. The question mark has a circular head and a long tail. Just try and see if it stands on your fingertip if you keep end of the long side of question mark on your finger? Can it stand? Of course, it cannot. The moment you remove your thumb, holdingthe question mark, away from it, it falls down. Needless to say that the whole body of a question mark cannot rest on just one end of it. Can you ever do it? Even if we allow; you to use any other thing along with this piece, can you make it stand on a fingertip? There is a trick to do it. See the question mark carefully. You will find a slot on the circular side of the question mark. Insert a
leather belt which boys often wear in this slot and try to balance it on your fingertip again.
Wow, it just happens!The question mark stands on your fingertip quite easily.
How does it happen?
We are all aware that earth's gravity acts on us and we are attracted towards the earth because of this gravitational pull. We can stand on the ground on our feet. Similarly, we can lie flat or even sit on the; ground. In all these postures, center of gravity of our body is well within the base of our body, giving it necessary stability. We may not be able to stand on single arm even if we attempt it. When we stand on one leg, we often lean on one side a little bit so that the centre of gravity passes through our standing leg. Now look at the Question Mark again. You can rest it on table comfortably on its flat surface. At the most, you may be able to keep it standing on its edge. However, it is impossible to make it stand on its one end. When we add belt to the question mark, overall scenario changes. If you look carefully, the slot in which the belt is inserted has a specific angle. As the belt is inserted, it is automatically tilted inside. Now we have to consider centre of gravity of not just the question mark, but belt and question mark together. As the belt is tilted inside, the C.G. also gets shifted inside. That means, it comes at the end of the question mark. This makes the question mark stand easily on its end. See if you can use any other object in place of a belt? What is Centre of Gravity? C.G. of a body is a fixed point through which the resultant force of gravity always passes, irrespective of the position of the body.