Vermicomposting involves degradation of organic matter into fertile manure by using special type of earthworms called as red worms. The nutrient rich manure is called as vermicompost. The process of preparing manure with the help of red worms is called vermicomposting. The red worm is a type of earthworm that lives in the soil rich in organic matter. Organic soils are rich in nitrogen and carbon with plenty of moisture and microbes.

The household wastes like paper, plastics, glass and metal objects present in the garbage can be recycled. These junk dealers send the discarded articles to the respective factories or mills for recycling. In order to recycle used and discarded materials, we should first separate our household garbage properly so that the waste materials which can be recycled do not get dumped alongwith other household garbage which is to be thrown away.

The path along which electricity can flow is called an electric circuit. A simple electric circuit can be made by using a cell, a torch bulb and two pieces of wire. A torch bulb is connected to the positive and negative terminal of the cell by using two pieces of wires called connecting wires. On connecting the torch bulb between the two terminals of a cell, the bulb lights up or glow because electricity flows through its filament.

The wires and the bulb form a continuous path between the two terminals of the cell. This path is called electric circuit. The bulb glows when electricity passes through the circuit.

A device that is used to break an electric circuit is called electric switch.
A switch is a simple device that either breaks the circuit or completes it. When switch is in ‘OFF’ position, then the circuit is open i.e. no current flows through the circuit and when switch is in ‘ON’ position, then the circuit is complete i.e. current flows through the circuit.

• Herbivores are the animals which eat only plants or plant products. For instance, cow, goat and buffalo are herbivores.
• Omnivores are the animals which eat both plants and animals. For instance, Bear, rodent, dog etc
• Carnivores are animals which eat flesh of other animals. eg tiger.lion etc

Cotton, hemp and linen produces a odour similar to that of burning paper on burning.

Advantages of friction
Friction plays a vital role in our daily life. Without friction we are handicap.
1. It is becomes difficult to walk on a slippery road due to low friction. When we move on ice, it     becomes difficult to walk due to low friction of ice.
2. We can not fix nail in the wood or wall if there is no friction. It is friction which holds the nail.
3. A horse can not pull a cart unless friction furnishes him a secure Foothold.
4. We can write on a paper or on a board.
5. Friction helps in applying the brakes.
6. It helps in walking on floor.
7. Coffee mug stays on the dashboard
8. Shuffling across a carpet to shock someone
9. Draging of atmosphire with earth is possible
10. Helps to pevents the life on earth by burning astroids.
Disadvantages of friction
Despite the fact that the friction is very important in our daily life, it also has some disadvantages like:
1. The main disadvantage of friction is that it produces heat in various parts of machines. In this way some useful energy is wasted as heat energy.
2. Due to friction we have to exert more power in machines.
3. It opposes the motion.
4. Due to friction, noise is also produced in machines.
5. Due to friction, engines of automobiles consume more fuel which is a money loss.
6. Machine efficency is decreased: energy input is lost to heat.

Evaporation: evaporation is a process where water changes into vapour. Evaporation occurs before a liquid reaches its boiling point. Evaporation can occur in all surfaces, at all times and at all places. Evaporation is frequent when the air is dry, hot and windy.
Condensation : Condensation is the opposite process where water vapour is converted to tiny droplets of water. Condensation is a phase change regardless of the temperature. Condensation takes place on salt, hygroscopic nuclei-pollen grains,carbon particles etc.when air temperature is decreased beyond the level of saturation.

Tearing of a paper is a physical change because when the paper is torn only the appearance of the paper is changed and no new substance is formed. Since this is a physical change this change can also be reversed.

Vermicomposting involves degradation of organic matter into fertile manure by using special type of earthworms called as red worms. The nutrient rich manure is called as vermicompost. The process of preparing manure with the help of red worms is called vermicomposting. The red worm is a type of earthworm that lives in the soil rich in organic matter. Organic soils are rich in nitrogen and carbon with plenty of moisture and microbes.

Since the use of plastic articles is not good for the environment, we should take some steps to save the environment. Some of them are as follows:

1. We should try to reduce the use of plastics like we should use bags made of cotton cloth or jute for shopping instead of using polythene bags.
2. We should not throw polythene bags, wrappers of chips, biscuits, etc. in water bodies, roads, in parks or picnic places. They should be put in dustbins.
3. We should reuse the plastic containers which come with jams, pickles, oil and other packed foods for storing salt, sugar, tea-leaves, etc.
4. Plastic wastes should be recycled so these should be sent to plastic making factories.