Last seen: Sep 30, 2021
A device, which utilises sun’s energy, is called a solar heating device. Example: Solar Cooker, Solar Heater, etc.
Wood is a renewable source of energy. It is obtained by cutting trees. A newly planted sapling usually takes more than 15 years to grow and mature int...
Natural gas is used (i) as a domestic and industrial fuel. (ii) in thermal power plants to generate electricity. (iii) as a fuel in vehicles lik...
The process of burning of a substance in the presence of air (oxygen) to produce heat and light is known as combustion. Conditions required for comb...
The ignition temperature of a splinter of wood is much lower than that of a log of wood. Thus, a match-stick can produce sufficient heat to reach the ...
Fossil fuels are formed by plants and animals in the course of millions of years. Fossil fuels are the energy rich compounds of carbon which were orig...
Bio-gas is produced by the anaerobic degradation of bio-mass in the presence of water but in the absence of air.
Technology provides the means to transform the energy of different sources into either a fuel or electricity.
The difference between the output energy and the input energy is usually referred to as the net energy or useful energy. For example, when we use fuel...
The energy that the earth receives from the sun, in the form of heat and light, is the ultimate source of almost all our source of energy.
When sand is poured over fire, the supply of air is cut off and the fire stops. When the supporter of combustion is cut off, then the combustion also ...
It is difficult to burn a wet piece of wood because water present in it keeps the temperature of wood below its ignition temperature.
Mass of cow dung = 210 g Mass of water, m = 50 g Specific heat of water, s = 4.2 J/g/°C Rise in temperature, t = 2 °C Heat produced Q = m × s ...
The three characteristics of a fuel that determines its quality are: (i) It should burn easily. (ii) It should cause least pollution in air. (ii...
LPG – Liquefied Petroleum Gas CNG – Compressed Natural Gas.
Asphalt and lubricating oil.
Petroleum gas is obtained as a by-product in oil refineries from the fractional distillation of petroleum. It is also produced by the cracking of petr...
Anthracite, Bituminous and Lignite.
Coal and Petroleum.
Methane is the main constituent of biogas.