Science Fair Project Models | Kids Science Experiments

Science becomes your gardener

Articles Required: A potted plant, a pot full of water, a piece of cotton string.

Many people are fond of indoor plants. But they hesitate to go in for them only because of the extra care they call for. For instance, who would look after them when the whole family is away on a vacation? At some places the neighbours might take care of them, but you don't always have such caring neighbours. Then what to do? Shouldn't one have indoor plants only because one likes to enjoy some vacation. Now go wherever you want to without worrying for your plants. In your absence, the science will take over the task of watering your plants. Well, get to know here how it's done.

Place your water container at some high place and put your potted plant somewhere near it, at the bottom, as shown in the figure here. Now take your cotton string and insert its one end in pot's soil and dip the other in the container. As you do it, the water will first start moving up through the string and then starts going down alongwith the string to the pot. In scientific terminology this phenomenon is called 'Capillary attraction'. As long as the water remains in the container it will keep on wetting the string and thus flowing out of it to water the plant. So the size of the water container should correspond to the time of your absence and the number of plants to be watered. Yes, remember one important thing: for each plant there should be a different string although the water container can remain the same.

Matchstick with sweet-tooth !

Articles Required: Amatchstick, a tub of water, sugar cube or sugar.

First of all, fill your tub with water. When the water surface is absolutely quiet and no bubbles are seen, just put a matchstick at the centre of the water surface. Now hang a sugar cube with thread at a distance of about three-four centimeters from the matchstick in such a manner that half of it remains submerged in the water. Yes, one thing: while handling these things take care not to create any disturbance in the water.

If you can't get a sugar cube, don't worry, you can just make a small pocket of sugar and hang it instead of the cube. After sometime you'll notice that the matchstick starts sliding towards the sugar cube, as if attracted by sweet. But do you know what is the actual reason behind it?

The sugar dissolves in water and makes a sweet solution. Being heavier than plain water, this sweet solution starts settling down. In this condition the water rushes from all directions to fill the gap. And as a result the matchstick is dragged along.

Colour absorbs heat !

Articles Required: An ice slab, four cloth-pieces of different colours (at least one black and one white) :- :-

Doesn't it sound strange that different colours absorb different amount of heat? Coming to think of it, what have colours to do with heat or cold ? But if you ponder a little deeply over it you would realise, that there is some weight in the argument. That's why we wear soft shades in summers and dark colours in winters.

How would you react if some friend calls it your whim and challenges you to prove it? Well, there is nothing to mind in that. After all'the basis of science is demonstration and experiment. So, how will you prove this to him? Come, we'll tell you here.

First of all, take a large slab of ice whose one surface is smooth and even. If it's not, make it so with the help of some hot object. Now take four rectangular cloth pieces, equal in size but in different colours. Yes, one of these must be white, one black and the other two of some other colours. Place them on the surface of ice as shown in the figure here and then put the ice slab in the sun for some time.

If the colours had no connection with heat whatsoever, it wouldn't have any special effect on the melting of ice. But it doesn't happen like this. After some time you notice that the ice has melted under the cloth pieces at different rate and the interesting fact to note is that the depth of these 'enclosures' is not the same under all four pieces.The maximum ice has melted from underneath the black cloth and the minimum under the white piece, and under the other ones depending upon their colour tones.

Magic Butterfly !

Articles Required: A • thin cardboard sheet, two small coins, adhesive tape, one broom-straw.

What about having a 'magic butterfly' that can sit on your fingertip without any support? Try making it today itself because it's very simple.
First of all, cut out a cardboard piece in the shape of a butterfly. Now paste a white paper on it and paint in pretty 'butterfly' colours.

Now paste a coin each under butterfly's two wings as shown in the figure. Also paste the broom straw right in its centre with its ends protruding a little from its mouth and tail. Well, your 'magic' butterfly is ready. If the coins have been pasted in such a way that its centre of gravity falls on the top of its head, it can be balanced on the tip of your forefinger very easily to enchant everybody present around you.

The Umbrella dance !

Articles Required: An umbrella with a "U" handle, a bottle in which umbrella handle can be inserted, string and a piece of chalk.

First rub the chalk on the string. Tie this string loosely to two points of opposite walls of a room. Now insert the umbrella handle in the bottle," and try to balance the bottle on this string. Once you've found the balancing point, your job is over. Now as you give it a light jerk it will start dancing like an acrobat—going up and down in a funny manner

The Dancing couple

Articles Required: Two long thin needles, a piece of cardboard, a pair of scissors,kfive pieces of cork (one big, four small) and camphor.

I Make a figure of a dancing couple on the cardboard. Cut it along its outline, and stick it on the bigger cork with glue.

Once it's firmly stuck, pierce two needles into the big cork making a 90° angle, to each other. Now on their four ends, insert small corks. Try to make the base as compact as possible. But in any case its diameter should never exceed 5 cm.

Stick camphor grains on the sides of four outer corks with the help of pins and place it on water surface. If it has been made as described above, the cardboard couple will turn around and move about—as if the couple has begun its waltz.

In order to have a flawless performance, you must remove all traces of oil from the container and corks. You can do this by washing these articles well with hot water mixed with soda.