skso7
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# skso7

 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## Demonstration of working principle of Rheostat in class room teaching in a simple way.

This improvised low cost apparatus made of mostly disposed material is very effective in teaching the working principle of a Rheostat when connected in a circuit.How the flow of electricity in a circuit changes with change in resistance can be  very conveniently explained while teaching the concept.

Flat nichrome wire from an old electric iron is wound spirally on an empty felt tip pen barrel leaving gaps between the windings with equal spacing.The length of the wire increases or decreases as we move up and down the barrel.A gem clip is used as a slider to go up and down the wire wound barrel.A 6v bulb is connected in the circuit along with a 9v dry cell.As the gem clip is slided up and the barrel one can observe the change in the intensity in the brightness of the bulb.

 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## Demonstration of standing wave in a string

In this improvised apparatus a 6v DC motor is taken and a small pulley is fixed to its shaft.A card board is cut in oval shape and fixed to the pulley at its centre.A small piece of of a plastic tongue cleaner isattached to one side of the motor.A piece of string is tied  to the free end of the tongue cleaner.When the motor runs,the ovl shaped cardboard makes the tongue cleaner vibrate to produce a stationery wave in the string.One can clearly observe the loops,nodes and antinodes of the standing wave in the string.

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 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## The factors that influence the resistance of a conductor

This is a low cost improvised science teaching learning aid to demonstrate that resistance of a conductor depends on some factors such as the length,cross sectional area,nature of the material of the conductor and temperature.An insulated wire,a copper wire,a flat nichrome wire and a round nichrome wire of the same length are taken.An iron spring that withstands temperature is also connected to a 6v bulb in the circuit.The intensity of the glow of the bulb indicates the variation in the resistance .

I designed this to show that the resistance of a conductor is directly proportional to its length,inversely proportional to its cross sectional area,the nature of the substance of which the conductor is made and inversely proportional to the temperature while teaching the concept in classroom.

 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## Enjoy the phenomena of Total Internal Reflection of a Light ray in a bottle.

Explaining the phenomena of total internal reflection of light to high school science students seem to be abstract without a proper teaching aid.When a light ray travels from one medium(denser)to another medium (rarer) it either refracts or reflects depending on the criticle angle of the first medium.

For this I took a medium size flat glass bottle.3/4th of it is filled with water.2-3 drops liquid soap is added to the water to make it slightly clowdy and to act as a dispersion medium for the passing light ray.A beam of light is flashed from a semi conductor laser torch on the sides of the glass bottle.When the light ray is flashed from a certain angle, I observed the reflection instead of refraction.Our students enjoyed this very much and many of them tried this on their own.

 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## Enjoy the phenomena of Total Internal Reflection of a Light ray in a bottle.

Explaining the phenomena of total internal reflection of light to high school science students seem to be abstract without a proper teaching aid.When a light ray travels from one medium(denser)to another medium (rarer) it either refracts or reflects depending on the criticle angle of the first medium.

For this I took a medium size flat glass bottle.3/4th of it is filled with water.2-3 drops liquid soap is added to the water to make it slightly clowdy and to act as a dispersion medium for the passing light ray.A beam of light is flashed from a semi conductor laser torch on the sides of the glass bottle.When the light ray is flashed from a certain angle, I observed the reflection instead of refraction.Our students enjoyed this very much and many of them tried this on their own.

 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## To demonstrate that CO2 is heavier than air.

This is a low cost innovative science learning aid.The children enjoy doing this experiment.With the help this they can easily demonstrate the property of carbon di oxide.

Two candels, one longer and one shorter,are fixed to inside botom of a small plastic dish 2 inches apart.A Small amount of lemon salt and a table spoon of baking soda(SODIUM BI CARBONATE) are placed in the container. Now the candles are lighted. Water is added in the container with the help of a dropper.Soon the reaction starts and CO2 is released. The flame of the shorter candle is put off.But the longer candle keeps glowing. CO2 prevails at the bottom of the dish displacing the air at the boyyomas it is heavir.So CO2 does not rise to the level of the longer candle So it keeps glowing till it is exhausted.

No comment yet.
 Rescooped by Sanjay Satheesh from Designing Improvised Innovative Low cost Science Teaching Learning Aids.

## Improvised 3-in-1 cup

This is a low cost improvised apparatus to teach and learn three science concepts in class room teaching.They are

1)Water Voltameter (electrolysis of water)

2) Conductivity Apparatus

3) Copper Voltameter

(electroplating)