WORK AND ENERGY How to calculate work Work

WORK AND ENERGY

How to calculate work? Work done = Force applied *distance moved § If distance moved=0 Therefore § Work Done=Force Applied ×

Different situations. Is work being done? Cooking and Painting Sleeping and Reading book

Energy Analysis Ø Work force and energy are interrelated. Ø Living Things get energy from food • Energy It is the capacity to do work • Some energy rich foods are: -

Sources of energy for non living things FUEL ENERGY WIND ENERGY AND SOLAR ENERGY WATER ENERGY-HYDRO ELECTRIC POWER STATION

Energy Sources • Renewable/Eco friendly/ Alternative • Non Renewable Fossil fuels

GEOTHERMAL ENERGY • Geothermal energy is produced by heat from the earth and is considered a form of renewable energy. It’s also considerably safer than most other energy sources. Unlike fossil fuel plants, geothermal power does not produce greenhouse gases that are harmful to the environment.

HYDROELECTRICITY • The energy of of falling water is used to drive turbines. • This in turn drives huge generators. • The energy of moving water is thus converted to electrical energy. • When water energy from tides is used to generate electricity, it is termed tidal energy. • Some Hydropower plants in India are Sardar Sarovar over Narmada, Bhakra Dam over Sutlej etc.

India is world’s 7 th largest producer of hydroelectric power

WIND ENERGY AND SOLAR ENERGY Sophisticated windmills used to generate electricity. Each solar cell generates a tiny electric current when hit by light. Hundreds of solar cells are joined together to form a solar panel.

FOSSIL FUELS WOOD COAL CRUDE OIL NATURAL GAS [LPG AND CNG] • GOBAR GAS MADE FROM COWDUNGIS USED FOR COOKING. • • • Biogas is a type of biofuel that is naturally produced from the decomposition of organic waste. When organic matter, such as food scraps and animal waste, break down in an anaerobic environment (an environment absent of oxygen) they release a blend of gases, primarily methane and carbon dioxide. •

NATURAL GAS • Natural gas is a non-renewable fossil fuel formed from the remains of tiny sea plants and animals that died 300 -400 million years ago. Approximately 90% of natural gas is composed of methane, but it also contains other gases such as propane and butane.

DIFFERENT FORMS OF ENERGY

HEAT ENERGY THERMAL ENERGY CAN OCCUR IN THREE WAYS

LIGHT ENERGY CHEMICAL ENERGY You must all know that we possess some kind of energy that helps us in getting through the day. The simple tasks you do on a daily basis require some amount of energy. Similarly, we refer to this energy as chemical energy. It releases when bonds are formed in a chemical reaction. It may be either exothermic or endothermic.

• Exothermic • Giving out heat • Burning of wood gives out heat • Endothermic • Absorbing Heat • When ice cubes are added to water heat is absorbed by the ice to cool the water.

EXOTHERMIC ENDOTHERMIC

SOUND ENERGY SOUND TRAVELS IN THE FORM OF WAVES

ENERGY CONVERSIONS-ENERGY CAN NEITHER BE CREATED NOR DESTROYED.