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प्रश्न
Write short note on Electrical energy generation and environment.
उत्तर
- Today, generating electrical energy has become essential. Life without electricity is unimaginable. Electrical energy is generated through various methods. A generator, based on the principle of electromagnetic induction, is used. The generator is rotated by a turbine, which is powered by energy sources.
- These energy sources can be renewable (e.g., wind, sunlight, nuclear fuels) or non-renewable (e.g., coal, petrol, water). Renewable sources like wind and sunlight are environmentally friendly and economical. They do not pollute the environment.
- However, non-renewable sources like coal, natural gas, and nuclear fuels harm the environment. Burning fossil fuels releases soot particles and greenhouse gases like carbon dioxide and carbon monoxide. These gases cause air pollution and contribute to global warming.
- Nuclear waste also emits harmful radiation, which affects both humans and the environment. We must find eco-friendly alternatives to fossil fuels. Switching to green energy sources is crucial to saving our planet.
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संबंधित प्रश्न
Why is the copper tube of a solar water heater painted black from outside?
Name the device which converts sunlight into electricity.
The radiations present in sunlight which make a solar cooker work are:
(a) visible light rays
(b) ultraviolet rays
(c) comic rays
(d) infrared rays
In order to make an efficient solar cooker, the cover of the cooker box should be made of:
If the solar constant is 1.4 kW/m2 then solar energy recived by 1m2area in one hour is:
(a) 5040 J
(b) 504.0 kJ
(c) 5040 kJ
(d) 5.04 kJ
In a solar water heater, why is the storage tank placed at a higher lever than the solar panel containing coils?
Solar cells are used to provide the electric current to charge the batteries of a car driven by an electric motor. Describe the energy changes which take place.
Name two devices which can be utilised for the cooking of food so as to save fuel.
Observe the connections of cells shown in the following images.
i. Which connection will give maximum potential difference?
ii. Give one advantage and one disadvantage of this energy.
Draw neat and labelled diagram.
One solar panel produces a potential difference of 18 V and current of 3 A. Describe how you can obtain a potential difference of 72 Volts and current of 9 A with a solar array using solar panels. You can use sign of a battery for a solar panel.
Re-write the statement by selecting the appropriate option.
The solar lamp uses the ................... energy.
Two statements are given - one labelled Assertion (A) and the other labelled Reason (R).
Assertion (A): A solar cooker cooks the meal due to the greenhouse effect.
Reason (R): The plane mirror is responsible for producing the greenhouse effect.
Make a table based on forms of energy and corresponding devices:
| Forms of Energy | Devices | |
| a. | Electric | _________ |
| b. | Mechanical | Sewing machine, Bicycle |
| c. | Thermal | __________ |
| d. | _________ | Solar cooker, Solar heater |
The power produced from solar cells is a DC.
The potential difference available from a solar cell depends on its area.
Complete the following flow chart.
What is the disadvantage of solar energy?
Choose the correct statement.
