P-2 Towards Green Energy Science - P-2 Towards Green Energy

The solar lamp uses the energy.

Which of the following is not the source of green energy?

Which of the following is used in solar cooker to harvest the solar energy?

What are the two technologies for harnessing solar energy?

Which is the most abundant and renewable energy?

………. energy of water in darns is used for generation of electricity.

……. energy of wind is used in wind mills.

Solar energy can be called ……. energy.

………. energy is a renewable source of energy.

Maximum energy generation in India is done using …………… energy.

 It is possible to produce energy from mW to MW using solar photovoltaic cells.

Hydroelectric energy, solar energy and wind energy are called renewable energies.

It is absolutely necessary to control the fission reaction in nuclear power plants.

The construction of turbine is different for different types of power plants.

Though the nuclear energy is extensive but the amount of electric power generations from nuclear power plant is much less.

Answer the following:

(a) Write the name of the device shown in the above diagram.
(b) Write briefly the work of this device.

(i) With reference to point B, potential energy of how much water reservoir in the dam will be converted into kinetic energy?

Explain the difference: Thermal electricity generation and Solar thermal electricity generation.

Explain the difference: Conventional and Non-conventional Sources of energy.

Remake the table taking into account relation between entries in three columns.

I	II	III
Coal	Potential energy	Wind electricity plant
Uranium	Kinetic energy	Hydroelectric plant
Water reservoir	Nuclear energy	Thermal plant
Wind	Thermal energy	Nuclear power plant

Draw a neat labelled diagrams: One solar panel produces a potential difference of 18 V and current of 3A. 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.

Draw a neat labelled diagrams: Energy transformation in solar thermal electric energy generation.

Give your opinion about whether hydroelectric plants are environment-friendly or not?

Draw a Schematic diagram of Solar thermal electric energy generation.

What are the advantages and limitations of solar energy?

The schematic of hydroelectric plant is shown in Figure. Water from about middle of the total height of the dam is taken to the turbine, as shown by point B in the diagram.

(i) With reference to point B, potential energy of how much water reservoir in the dam will be converted into kinetic energy?
(ii) What will be the effect on electricity generation, if the channel taking water to turbine starts at point A?
(iii) What will be the effect on electricity generation, if the channel taking water to turbine starts at point C?

Read the information given below and solve the questions based on it.
Electric energy is produced in various ways like hydroelectric, wind power, solar energy, bio-fuel, etc. These energy sources are inexhaustible, sustainable. Besides, it does not cause any environmental problem.
Questions and Answers:
(1) Above information is about which type of energy?
(2) Whether the fossil fuel is an example of this energy?
(3) Draw the flow chart of production of electric energy.

Renewable energy is, energy produced from sources that do not deplete or can be replenished within a human’s life time. The most common examples include wind, solar, geothermal, biorhass, and hydroelectric power. This is in contrast to non-renewable sources such as fossil fuels. Most renewable energy is derived directly or indirectly from the sun. Sunlight can be captured directly using solar technologies. The sun’s heat drives winds, whose energy is captured with turbines. Plants also rely on the sun to grow and their stored energy can be utilized for bioenergy. Not all renewable energy sources rely on the sun. For example, geothermal energy utilizes the Earth’s internal heat, tidal energy relies on the gravitational pull of the moon, and hydroelectric power relies on the flow of water.
Questions and Answers :
(1) What is renewable energy?
(2) Give the examples of renewable energy.
(3) Why will energy from fossil fuel be over soon?
(4) Name the renewable sources of energy which are not dependent on sun. What are they dependent upon?
(5) Which type of energy do we mostly use in India?

Write a short note on Electrical energy generation and environment.

Explain with diagram step-by-step energy conversion in Hydroelectric power plant:

The power available from the solar cells is AC.

The potential difference available from a solar cell is independent of its area.

The machine which converts the potential energy of wind to electrical energy is called wind-turbine.

Use of energy is unavoidable in our daily life, but we must use it carefully and only in the required amount.

The turbine is connected to electric generator, therefore the magnet rotates and electric energy is thus produced.