EARLY MAN DID NOT KNOW WHAT FIRE WAS BUT HE WAS WELL AWARED OF THE DESTRUCTION CAUSED BY FIRE.SO HE...

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Transcript of EARLY MAN DID NOT KNOW WHAT FIRE WAS BUT HE WAS WELL AWARED OF THE DESTRUCTION CAUSED BY FIRE.SO HE...

EARLY MAN DID NOT KNOW WHAT FIRE WAS BUT HE WAS WELL AWARED OF THE DESTRUCTION CAUSED BY FIRE.SO HE WAS AFRAID OF FIRE.

FIRE IS THE RESULT OF A CHEMICAL REACTION.WHEN THE OXYGEN IN THE AIR COMBINES WITHCARBON AND HYDROGEN IN A FUEL,A CHEMICAL REACTION TAKES PLACE.ENERGY IN THE FORM OF HEAT AND LIGHT IS RELEASED IN THIS PROCESS.THIS IS WHAT WE CALLED FIRE.

OXYGEN

HEAT

FUEL

COOKINGGAS

PETROL

WOOD COAL

                                                                                           

Forest FireIn this picture a fire rages through Yellowstone National Park in the United States. There are three kinds of forest fires: one that burns a layer of the forest floor only, one that burns surface litter and forest undergrowth, and one that advances through the tops of trees. All three fires can occur at the same time.

The Stock Market/J.B. Diederich/ContactMicrosoft ® Encarta ® Encyclopedia. © 1993-2004 Microsoft Corporation. All rights reserved.

                                                                                           

Forest FireIn this picture a fire rages through Yellowstone National Park in the United States. There are three kinds of forest fires: one that burns a layer of the forest floor only, one that burns surface litter and forest undergrowth, and one that advances through the tops of trees. All three fires can occur at the same time.

The Stock Market/J.B. Diederich/ContactMicrosoft ® Encarta ® Encyclopedia. © 1993-2004 Microsoft Corporation. All rights reserved.

A GOOD SERVENT ANDA BAD MASTER.

WE USE FIRE TO ---1.COOK FOOD.2.WARM OUR HOUSES.3.TO KEEP OURSELVES

WARM IN WINTER.

WHEN IT GETS OUT OF CONTROL,IT CAN CAUSE A LOT OF DESTRUCTIONVAST AREAS OF FOREST ARE DESTROYED BY FIRE.

1.BY TAKING AWAY THE FUEL.IF THE FIRE HAS NO FUEL TO FEED ON,NO BURNING CAN TAKE

PLACE.2.BY PREVENTING OXYGEN SUPPLY.NO SUPPLY

OF OXYGEN MEANS NO FIRE.3.SMALL FIRES CAN BE PUT OUT WITH A BLANKET

OR A SAKE.4.BY REMOVING THE HEAT.IF THE TEMPERATURE

IS BELOW THE FLASH POINT,THE FUEL STOPS

BURNING.

5.SOMETIMES WATER IS SPRAYED ON A FIRE.IT ABSORBS HEAT FROM THE BURNING FUEL AND LOWERS THE TEMPRATURE 6.SOME FIRES CAN NOT BE PUT OUT WITH WATER.IF WATER IS SPRAYED ON TO AN OIL FIRE,THE OIL WILLFLOAT TO THE TOP OF THE WATER AND CONTINUE TO BURN IT CAN BE VERY DANGEROUS.7.WATER SHOULD ALSO NOT BE USED ON FIRES CAUSED BY ELECTRICAL APPLIANCES.THE PERSON SPRAYING WATER MIGHT GET AN ELCTRIC SHOCK AND BE KILLED.

• 8.A CARBONDIOXIDE EXTINGUISHER IS THE BEST THING TO FIGHT AN ELECTRICAL AND AN OIL FIRE.

• 9.LASTLY,WE CAN CALL THE FIRE FIGHTERS.THEY ARE HIGHLY TRAINED PEOPLE .THEY CUT OFF ELECTRICITY SUPPLY,KNOCK DOPWN DANGEROUS WALLS,SPRAY WATER AND OTHER MATERIALS TO BRING FIRE UNDER CONTROL.