Science and Technology II · Textbook solutions

Towards Green Energy

Every solved example, exercise, and miscellaneous question, in the order the textbook teaches them. Plus every board question asked from this chapter. · 29 questions

Exercise

29 q

Ex Q1 $Remake the table taking into account relation between entries in three columns. I II III Coal Potential energy Wind electricity plant Uranium Kinetic Energy Hydro electric plant Water Reservoir Nuclear Energy Thermal plant Wind Thermal Energy Nuclear power plant$
Ex Q2 $Which fuel is used in thermal power plant? What are the problems associated with this type of power generation?$
Ex Q3 $Other than thermal power plant, which power plants use thermal energy for power generation? In what different ways is the thermal energy obtained?$
Ex Q4 $Which type/types of power generation involve maximum number of steps of energy conversion? In which power generation is the number minimum?$
Solve the following crossword puzzle.
Ex Q5(a) $Maximum energy generation in India is done using..... energy.$
Ex Q5(b) $...... energy is a renewable source of energy$
Ex Q5(c) $Solar energy can be called.... energy.$
Ex Q5(d) $.... energy of wind is used in wind mills.$
Ex Q5(e) $..... energy of water in dams is used for generation of electricity.$
Explain the difference.
Ex Q6(a) $Conventional and Non-conventional Sources of energy.$
Ex Q6(b) $Thermal electricity generation and solar thermal electricity generation.$
Ex Q7 $What is meant by green energy? Which energy sources can be called as green energy sources and why? Give example.$
Explain the following sentences.
Ex Q8(a) $Energy obtained from fossil fuels is not green energy.$
Ex Q8(b) $Saving energy is the need of the hour.$
Answer the following questions.
Ex Q9(a) $How can we get the required amount of energy by connecting solar panels?$
Ex Q9(b) $What are the advantages and limitations of solar energy?$
Explain with diagram step-by-step energy conversion in
Ex Q10(a) $Thermal power plant$
Ex Q10(b) $Nuclear Power Plant$
Ex Q10(c) $Solar thermal power plant$
Ex Q10(d) $Hydroelectric power plant$
Give scientific reasons
Ex Q11(a) $The construction of turbine is different for different types of power plants.$
Ex Q11(b) $It is absolutely necessary to control the fission reaction in nuclear power plants.$
Ex Q11(c) $Hydroelectric energy, solar energy and wind energy are called renewable energies.$
Ex Q11(d) $It is possible to produce energy from mW to MW using solar photovoltaic cells.$
Ex Q12 $Draw a schematic diagram of solar thermal electric energy generation.$
Ex Q13 $Give your opinion about whether hydroelectric plants are environment friendly or not?$
Draw neat and labelled diagrams.
Ex Q14(a) $Energy transformation in solar thermal electric energy generation.$
Ex Q14(b) $One solar panel produces a potential difference of 18 V and current of 3A. Describe how you can obtain a potential difference of 72 Volts and current of 9 A with a solar array using solar panels. You can use sign of a battery for a solar panel.$
Ex Q15 $Write short note on Electrical energy generation and environment.$

I	II	III
Coal	Potential energy	Wind electricity plant
Uranium	Kinetic Energy	Hydro electric plant
Water Reservoir	Nuclear Energy	Thermal plant
Wind	Thermal Energy	Nuclear power plant

What the board has asked from this chapter

Questions per paper · 11 papers · 2017 to 2026

June 2026

4 q

Q1(A)(v) $आंध्रप्रदेशातील श्रीशैलम येथे ____ विद्युत केंद्र आहे. Srishailam in Andhra Pradesh has ____________ energy power plant.$
Tap an option to check your answer.
Renewable and Non-Renewable Energy
खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा :
Draw the flow chart showing step by step energy transformation in the following power plants.
Q4(ii)(a) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : औष्णिक विद्युत निर्मिती केंद्र Thermal Power Plant$
Energy Sources
Q4(ii)(b) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : अणु विद्युत निर्मिती केंद्र Nuclear Power Plant$
Energy Sources
Q4(ii)(c) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : सौर विद्युत निर्मिती केंद्र Solar Power Plant.$
Green Energy Technologies

March 2026

3 q

Q1(A)(iv) $महाराष्ट्रातील ____ येथे प्रमुख जलविद्युत निर्मिती केंद्र आहे. In Maharashtra the major hydroelectric power plant is located at ____________.$
Tap an option to check your answer.
Renewable and Non-Renewable Energy
Q2(B)(iv) $जल-विद्युत निर्मितीचे दोन फायदे लिहा. Write any two advantages of hydroelectric power generation.$
Renewable and Non-Renewable Energy
Q3(iv) $औष्णिक विद्युत निर्मितीमध्ये कोणते इंधन वापरतात ? या विद्युत निर्मितीमुळे निर्माण होणाऱ्या समस्या कोणत्या ? Which fuel is used in a thermal power plant? What are the problems associated with this type of power generation?$
Renewable and Non-Renewable Energy

July 2025

2 q

Q1(B)(iv) $\to$
Green Energy Technologies
Q3(iv) $\to$
Energy Sources

March 2025

3 q

Q1(A)(v) $सौर विद्युत घट सूर्यकिरणातील प्रकाश ऊर्जेचे रूपांतर सरळपणे ____ करतात. Solar photovoltaic cell converts the solar radiation energy directly into ____ energy.$
Tap an option to check your answer.
Green Energy Technologies
Q2(A)(iii) $शास्त्रीय कारणे लिहा : अणु ऊर्जेपासून मिळणारी ऊर्जा पर्यावरणस्नेही नाही. Give scientific reason: The energy generated from nuclear fuels is not environment friendly.$
Renewable and Non-Renewable Energy
Q3(iv) $औष्णिक विद्युत निर्मितीमुळे कोणते इंधन वापरतात ? या विद्युतनिर्मितीमुळे निर्माण होणाऱ्या कोणत्याही दोन समस्या स्पष्ट करा. Which fuel is used in thermal power plant? Write any two problems associated with this type of power generation.$
Energy Sources

July 2024

2 q

Q1(A)(iii) $वाहत्या वाऱ्यातील गतिज ऊर्जेचे विद्युत ऊर्जेत रूपांतर करणाऱ्या यंत्राला ____ असे म्हणतात. The machine which converts the kinetic energy of wind to electrical energy is called ____.$
Tap an option to check your answer.
Green Energy Technologies
Q3(v) $पुढील आकृतीचे निरीक्षण करा व विचारलेल्या प्रश्नांची उत्तरे लिहा : (अ) वरील आकृतीत कोणत्या ऊर्जेवर आधारित विद्युत निर्मिती होते ? (आ) या विद्युत निर्मिती केंद्रात कोणते इंधन वापरले जाते ? (इ) या प्रकारच्या विद्युत निर्मिती करण्यात येणाऱ्या समस्यांपैकी एक समस्या लिहा. Observe the diagram and answer the following questions: (a) Which type of energy is created in the above diagram? (b) Which type of fuel is used in power plant? (c) State one problem created in such type of power plant.$
Energy Sources

March 2024

4 q

Q1(A)(iv) $महाराष्ट्रात ____ हे प्रमुख अणुऊर्जा निर्मिती केंद्र आहे. The atomic power plant in Maharashtra is ____.$
Tap an option to check your answer.
Energy Sources
Q2(A)(ii) $शास्त्रीय कारणे लिहा : जलविद्युत ऊर्जा, सौर ऊर्जा आणि पवन ऊर्जा यांना नूतनीकरणक्षम ऊर्जा म्हणतात. Give scientific reason: Hydroelectric energy, solar energy and wind energy are called renewable energies.$
Renewable and Non-Renewable Energy
Q2(B)(i) $किरणोत्सारी प्रदूषणाचे मानवी शरीरावर होणारे कोणतेही चार दुष्परिणाम लिहा. Write four adverse effects of radiations on the human body.$
Energy Sources
Q3(iv) $दिलेल्या आकृतीचे निरीक्षण करून खालील प्रश्नांची उत्तरे लिहा. प्रश्न : (अ) दिलेली आकृती कशाची आहे, ती ओळखा. (ब) या प्रकल्पात ऊर्जेचा स्रोत कोणता ? (क) या स्रोतास ‘पर्यावरणस्नेही स्रोत’ का म्हणतात ? Observe the given picture and answer the questions: (a) Identify the given diagram. (b) What is the source of energy in this project? (c) Why is this source supposed to be eco-friendly?$
Green Energy Technologies

March 2023

7 q

Q1(A)(iv) $The Hydroelectric capacity of Koyna dam is ____.$
Tap an option to check your answer.
Renewable and Non-Renewable Energy
Q2(A)(ii) $Give scientific reason: It is absolutely necessary to control the fission reaction in a nuclear power plant.$
Energy Sources
Q2(B)(v) $What are the benefits of mixing ethanol with petrol and diesel?$
Green Energy Technologies
Refer to the figure of a hydroelectric power station showing the reservoir wall with three marked levels — A (top), B (middle) and C (bottom) — the sluice gate, penstock, turbine, generator and power house.
Q3(iv)(a) $With reference to point B, the potential energy of how much water in the reservoir of the dam will be converted into kinetic energy?$
Energy Sources
Q3(iv)(b) $What will be the effect on electricity generation if the channel taking water to the turbine starts at point A?$
Energy Sources
Q3(iv)(c) $What will be the effect on electricity generation if the channel taking water to the turbine starts at point C?$
Energy Sources
Q3(vii) $Which fuels are obtained from biomass?$
Renewable and Non-Renewable Energy

March 2022

6 q

Q1(B)(iv) $Which type of fuel is used in thermal power plant?$
Energy Sources
Q2(A)(iii) $Give scientific reason: Power generation plant based on natural gas is eco-friendly.$
Energy Sources
Refer to the cyclic picture showing: 'Solar energy + $\text{CO}_2$ ' absorbed by trees (Biomass), then Harvesting, Threshing, Cellulose, 'Conversion of cellulose to glucose', Sugars, 'Liquid fuel production through fermentation', Biofuel used in a car, a truck and an aeroplane, each releasing $\text{CO}_2$ which returns to the plants.
Q3(vii)(1) $Which process is shown in the above given picture?$
Energy Sources
Q3(vii)(2) $Give two examples for liquid fuels and solid fuels obtained by this process.$
Renewable and Non-Renewable Energy
Printed on the paper as sub-question 'vi.' of Q.3, but 'vi.' has already been used earlier in Q.3 (Darwin's theory), so this is the eighth sub-question of Q.3 — a printing/numbering error in the source paper.
Q3(viii)(1) $Complete the stages in electric generator using wind energy (a flow chart of four boxes joined by arrows).$
Renewable and Non-Renewable Energy
Q3(viii)(2) $Write limitations in an electric generator using wind energy.$
Renewable and Non-Renewable Energy

March 2020

3 q

Q1(A)(iii) $Incomplete combustion of fuels leads to formation of ____$
Tap an option to check your answer.
Energy Sources
Q2(B)(i) $Complete the following chart showing the 'Effect of Radioactive Pollution' by writing the appropriate effect in each of the four blank boxes.$
Energy Sources
Q3(vii) $Make a table based on forms of energy and corresponding devices by completing the blanks: Forms of Energy Devices a. Electric____b. Mechanical Sewing machine, Bicycle c. Thermal____d.____Solar cooker, Solar heater$
Energy Sources

	Forms of Energy	Devices
a.	Electric	____
b.	Mechanical	Sewing machine, Bicycle
c.	Thermal	____
d.	____	Solar cooker, Solar heater

March 2019

5 q

Q1(A)(i) $Identify the process shown in the figure and name it.$
Energy Sources
Q2(iii) $What are the advantages of hydroelectric power generation?$
Renewable and Non-Renewable Energy
Observe the diagram of the power plant and answer the questions.
Q3(iv)(a) $Which energy is generated from the power plant?$
Energy Sources
Q3(iv)(b) $State its source.$
Energy Sources
Q3(iv)(c) $Which is more eco-friendly — power generation from coal or power generation from natural gas? Why?$
Energy Sources

March 2017

2 q

Attempt any five of the following.
Q2(4) $What is recycling? Give one example.$
Green Energy Technologies
Attempt any five of the following questions.
Q3(2) $What is the need to use eco-friendly technology?$
Green Energy Technologies

The 10 board questions to practise first

The questions the board asked again come first, most asked first. Each one says how often and when.

Question 1
Asked 3 times: Mar 2022*, Mar 2025, Mar 2026 (* = numbers or wording changed that year)
Q3(iv) $औष्णिक विद्युत निर्मितीमध्ये कोणते इंधन वापरतात ? या विद्युत निर्मितीमुळे निर्माण होणाऱ्या समस्या कोणत्या ? Which fuel is used in a thermal power plant? What are the problems associated with this type of power generation?$
Question 2
Asked 2 times: Mar 2019, Mar 2026
Q2(B)(iv) $जल-विद्युत निर्मितीचे दोन फायदे लिहा. Write any two advantages of hydroelectric power generation.$
Question 3
Asked 2 times: Mar 2023, Mar 2026* (* = numbers or wording changed that year)
Q1(A)(iv) $महाराष्ट्रातील ____ येथे प्रमुख जलविद्युत निर्मिती केंद्र आहे. In Maharashtra the major hydroelectric power plant is located at ____________.$
Tap an option to check your answer.
Question 4
This type asked 7 times: Mar 2019, Mar 2020, Mar 2023, Mar 2024, Jul 2024, Jul 2025, Jun 2026. This one: Jun 2026
Draw the flow chart showing step by step energy transformation in the following power plants.
Q4(ii)(a) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : औष्णिक विद्युत निर्मिती केंद्र Thermal Power Plant$
Question 5
This type asked 6 times: Mar 2022, Mar 2024, Jul 2024, Mar 2025, Jul 2025, Jun 2026. This one: Jun 2026
Draw the flow chart showing step by step energy transformation in the following power plants.
Q4(ii)(c) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : सौर विद्युत निर्मिती केंद्र Solar Power Plant.$
Question 6
This type asked 4 times: Mar 2020, Mar 2023, Mar 2024, Mar 2025. This one: Mar 2025
Q2(A)(iii) $शास्त्रीय कारणे लिहा : अणु ऊर्जेपासून मिळणारी ऊर्जा पर्यावरणस्नेही नाही. Give scientific reason: The energy generated from nuclear fuels is not environment friendly.$
Question 7
This type asked 4 times: Mar 2017, Mar 2020, Mar 2022, Mar 2024. This one: Mar 2024
Q2(A)(ii) $शास्त्रीय कारणे लिहा : जलविद्युत ऊर्जा, सौर ऊर्जा आणि पवन ऊर्जा यांना नूतनीकरणक्षम ऊर्जा म्हणतात. Give scientific reason: Hydroelectric energy, solar energy and wind energy are called renewable energies.$
Question 8
This type asked 2 times: Mar 2022, Mar 2023. This one: Mar 2023
Q3(vii) $Which fuels are obtained from biomass?$
Question 9
Asked once: Jun 2026 (same type asked 7 times)
Draw the flow chart showing step by step energy transformation in the following power plants.
Q4(ii)(b) $खालील विद्युत निर्मिती केंद्रात टप्प्याटप्प्याने होणारे ऊर्जा रूपांतरण स्पष्ट करणारी प्रवाह आकृती काढा : अणु विद्युत निर्मिती केंद्र Nuclear Power Plant$
Question 10
Asked once: Jul 2025 (same type asked 6 times)
Q1(B)(iv) $\to$

Exercise

What the board has asked from this chapter

June 2026

March 2026

July 2025

March 2025

July 2024

March 2024

March 2023

March 2022

March 2020

March 2019

March 2017

The 10 board questions to practise first

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10