Last seen: Sep 30, 2021
Coal and petroleum are rich sources of energy and it takes millions of years for their formation. As these resources are being consumed in ever increa...
1. Switch off lights and fans when not required. 2. Use of solar radiation for cooking food and lighting. 3. Use of fluorescent tubes or CFL. 4....
Because of the excessive use of fertilisers in the fields, they were carried down to the lake during rains. The fertilisers contain phosphates and nit...
Two advantages of water harvesting at the community level are: Water can be stored during rainy season and can be used when required. Groundwater...
To allow rainwater to recharge groundwater by water harvesting is the better option. Its advantages are: (i) Groundwater does not evaporate. (i...
Chipko Movement: During 1970, in Reni village of Garhwal, a contractor was allowed to cut trees in a forest near the village. When the contractor...
Biodiversity is measured by the number of different life forms found in an area. In a forest, various species exist which include bacteria, fungi, fer...
‘Sustainable management’ is the management of resources in which development can be maintained for a long time without undue damage to the environment...
When fossil fuels are burnt, carbon dioxide, water, oxides of nitrogen and oxides of sulphur are formed. If the combustion takes place in insufficient...
Three problems of construction of large dams are: Displacement of large number of people. Huge cost of construction and low benefit compared to c...
Fossil fuels like coal and petroleum are formed from biomass. In addition to carbon, they contain hydrogen, nitrogen and sulphur. When fossil fuels ar...
Four advantages of storing water in the ground are: It does not evaporate. It is relatively protected from contamination by human and animal wast...
Equitable distribution of resources means ensuring benefits from the development of resources to all human beings. There should be equitable distrib...
(i) The material contained in the bodies of plants and animals is called biomass. (ii) Breakdown of organic matter by micro-organisms when oxygen is...
1. Geothermal energy, wind energy 2. Coal, petroleum
Disadvantages: Fossil fuels cause pollution. They also cause acid rain. They disturb ecology. They cannot be reused, i.e. they are non-renewabl...
Sources which are. not available again and again and are getting exhausted and are called non-renewable sources of energy, e.g. coal, petroleum.
Four characteristics of a good fuel are: Higher calorific value Lesser pollution Sustainable for longer period Easily transportable
(i) Local people who live around forests: They use forests for grazing their cattles, collecting fruits, firewood, bamboo and thatch. (ii) Industria...
(i) By switching off unnecessary lights and fans. This will reduce consumption of coal in production of electricity. (ii) By using public transport ...