examples of primary sources and secondary sources

Source of Electricity - Electrons in different metals can have different energies. If two of these metals are placed in a conducting liquid (electrolyte) a difference in electrical potential is set up between them. A pair of different metals arranged in this way is an electrochemical cell..

The Sun radiates energy in the form of heat and light. We utilize these forms of energy either directly or indirectly, after conversion into some other forms. Utilization of solar energy in various ways is as represented. Besides the primary role of the Sun's energy, it is now believed t..

Rich sources of Niacin are liver, yeast, whole grains, cereals and pulses. Milk, fish, eggs and vegetables are the moderate sources of niaci..

Rich sources of vitamin B 6 are egg, fish, milk and meat. Wheat, corn, cabbage, roots and tubers are some other sources of vitamin B ..

The common sources of fats are butter, ghee, cheese, meat, egg yolk, milk, nuts, et..

Good sources are cereals, pulses, nuts and yeast. Thiamine is mostly found in outerlayer of cereals. It is also found in pork, liver, heart, kidney, milk, et..

of Proteins are of both animal and plant origin. Some of the common sources are groundnuts, beans, whole cereals, pulses. among plants and fish, egg, meat, milk, cheese among animal product..

Household gadgets like mixer, grinder, vacuum cleaner, washing machine, cooler, air conditioners, greatly enhance the levels of sound and are deleterious to health. Loud speakers not only disturb the students in their studies but also the peace of the locality. Loud radios, stereos and televis..

Some of the most common sources of wastes are as follows: Domestic wastes Commercial wastes Ashes Animal wastes Biomedical wastes Construction wastes Industrial Solid Wastes Sewe..

Sewage that includes organic matter, animal and human excreta-one of the major pollutants of water in the urban and rural areas is the sewage. The sewage most often contains the organic matter that encourages the growth of microorganisms. These organisms besides spreading diseases also consume the..