NCERT Solutions for Class 10 English Main Course Book (MCB) Chapter 10
Unit-3 : Solutions of Questions on Page Number : 88
NCERT Solutions for Class 10 English Main Course Book (MCB) Chapter 10
Q1 : In A.2 you will read about alternate sources of energy. Before doing so find out how much you already know about renewable sources of energy.
Complete column A, to indicate whether you think each statement is True (), False(X), or whether you do not know (?) After reading the passage, complete column B in the same way.
statements | (A) | (B) | |
| (a) | Solar energy is a powerful source of energy | ||
| (b) | Electric battery operated cars are more powerful than those run on fossil fuels | ||
| (c) | EV stands for electric vehicles | ||
| (d) | Driving an electric vehicle is stressful | ||
| (e) | Solar power can be the next source of pollution in the world | ||
| (f) | India is one of the countries with a great potential for generation and use of solar energy | ||
| (g) | Using alternate s | ||
Answer :
statements | (A) | (B) | |
| (a) | Solar energy is a powerful source of energy | True | |
| (b) | Electric battery operated cars are more powerful than those run on fossil fuels | False | |
| (c) | EV stands for electric vehicles | True | |
| (d) | Driving an electric vehicle is stressful | False | |
| (e) | Solar power can be the next source of pollution in the world | False | |
| (f) | India is one of the countries with a great potential for generation and use of solar energy | True | |
| (g) | Using alternate sources of energy can help India save a lot of money spent in foreign exchange | True | |
Q2 : Now go back to A.1 and complete column (B). How much did you know already before you read the article?
Answer :
statements | (A) | (B) | |
| (a) | Solar energy is a powerful source of energy | True | True |
| (b) | Electric battery operated cars are more powerful than those run on fossil fuels | False | False |
| (c) | EV stands for electric vehicles | True | True |
| (d) | Driving an electric vehicle is stressful | False | False |
| (e) | Solar power can be the next source of pollution in the world | False | False |
| (f) | India is one of the countries with a great potential for generation and use of solar energy | True | True |
| (g) | Using alternate sources of energy can help India save a lot of money spent in foreign exchange | True | True |
Q3 : India receives 5000 trillion KWH / year which means______________________
Answer :
Production is far more than the total annual consumption. Besides, as solar energy is a renewable source of energy, considering its environmental and economic cost, it is far cheaper than non-renewable fossil fuel resources.
Q4 : The advantages of using solar energy instead of fossil fuels is that it is______________________
Answer :
Not only a renewable and clean source of energy rather works cheaper than fossil fuel resources. Solar energy can be converted into solar power through many technologies, thus making this abundantly available source of energy viable for the next 1000crore years. Solar photovoltaic (SPV) technology, photo galvanic cells, solar steam generators (solar concentrating power), solar tower or solar chimney, radio micrometers and thermopile are some of the technologies which can be used for the purpose.
Q5 : It is important to find means of keeping air and noise pollution in urban areas under control because______________________
Answer :
It is estimated that by 2020, India’s urban population will grow five fold to a staggering 200 million. As the flourishing population and rising economic activity lead to tremendous rise in transport sector, pollution is expected to grow seven times. The formidable future with no clean air to breathe and smog-filled concrete jungles is inevitable if measures such as alternate-fuel vehicles are not adopted in time.
Q6 : Tax exemptions and subsidies are required to______________________
Answer :
Make electric vehicles (EVs) popular in India. A holistic approach involving the government, public and auto majors is needed. Appropriate government policies during the next five years and adequate support from business houses and institutions will go a long way in promoting the industry in India.
Q7 : Tax exemptions and subsidies are required to______________________
Answer :
Make electric vehicles (EVs) popular in India. A holistic approach involving the government, public and auto majors is needed. Appropriate government policies during the next five years and adequate support from business houses and institutions will go a long way in promoting the industry in India.
Q8 : The media can help by______________________
Answer :
Playing its role in educating the public about alternate fuel vehicles and their advantages. People need to be informed more about these technologies and their advantages so that they can be brought to practice as soon as possible and this constant fear of being destitute of nature nags us no more.
Q9 : Copy and complete the following table with the required information from the passage
Points of comparison | Internal Combustion | Engine Electric Motors | |
| 1. | Pollution | ||
| 2. | Engine efficiency | ||
| 3. | Peak power generation | ||
| 4. | Recharging | ||
| 5. | Maintenance | ||
Answer :
The completed table is given below;
Points of comparison | Internal Combustion Engine | Electric Motors | |
| 1. | Pollution | Internal combustion engines (ICEs) produce air pollution due to incomplete combustion of fuel. Other than exhaling major amount of Carbon Dioxide (CO2), some amount of nitrogen oxide and sulphur plus some hydrocarbons that are not combusted completely and they emit water and soot. | If we can have three lakh electric vehicles (EVs) on the roads by 220 including three wheelers, cars and scooters, we would have reduced pollution by 16 lakh metric tonnes. |
| 2. | Engine efficiency | Internal combustion engine vehicles can convert about 20% of the chemical energy in gasoline into useful work. | 75% or more of the energy from a battery has productive power in an electric vehicle.The electric vehicle uses electric energy which is stored in batteries that feed the electric motor. An electric vehicle has no speed-gear and functioning noise. It is enough to turn the key and press the acceleration pedal; one needs only two driving pedals-accelerator and brake. |
| 3. | Peak power generation | ICEs must be revved up to high rpm to achieve maximum power | Electric motors provide nearly peak power even at low speeds. This gives electric vehicles strong acceleration performance from a stop. |
| 4. | Recharging | ICEs are fuel-dependent. There is an internal combustion of any of LPG, CNG or petrol and diesel for generation of power. | The cost and performance of EVs are driven by newer batteries. There are several major types of automotive batteries available and under development, from advanced lead acid batteries like those that start our internal combustion engines to lithium polymer batteries. Although recharging could be a consideration, home recharging systems are available giving EVs an added advantage. |
| 5. | Maintenance | In conventional vehicles, the pollution increases with degradation of engine, poor maintenance of engine and adulterated fuel. | EVs do not degrade with time and they are always zero polluting. Thus, they are easy to handle and have low maintenance costs. |
Q10 : Based on your reading of the passage say whether the following statements are True or False:
(a) EVs have the potential to flourish in India
(b) EVs degrade with time
(c) EVs can create health hazards
(d) EVs cannot drive fast because they have only two pedals
(e) Solar power will not last for a very long time in our country
(f) Establishing Solar Power generating units is too expensive
Answer :
(a) True
(b) False
(c) False
(d) False
(e) False
(f) False
Q11 : Below is a flow chart describing the process of making rubber. Use it to help you copy and complete the process description that follows it. Remember to use the simple present tense, a mixture of actives and passives, and to add sequence markers where you see*
Plant rubber trees | → | Make cuts in the bark and attach containers. | → | Collect latex in the containers | → | Send latex to the factory |
| Coagulate latex with acetic acid. | → | Separate the coagulated mass | → | Press it into blocks or roll it into sheets | → | Dry the blocks or sheets in a current of warm air |
First rubber trees …….. in deep soil.*. When the trees …, fully ….., the bark of the tree …. and containers …. The latex …….. and is ……. to the factory. Here it ….. by treating it with acetic acid* the coagulated mass ….. It is then ….. into blocks or ….. into sheets. * …. in a current of warm air. Check: What tense did you use? Did you use sequence markers? Did you use a mixture of actives and passives?
Answer :
Plant rubber trees | → | Make cuts in the bark and attach containers. | → | Collect latex in the containers | → | Send latex to the factory |
| Coagulate latex with acetic acid. | → | Separate the coagulated mass | → | Press it into blocks or roll it into sheets | → | Dry the blocks or sheets in a current of warm air |
The description in the required form is given below:
First rubber trees are planted in deep soil.*. When the trees huge, fully grown, the bark of the tree is cut and containers are attached. The latex is collected in the containers and is sent to the factory. Here it is coagulated by treating it with acetic acid* the coagulated mass is separated. It is then pressed into blocks or rolled into sheets. * The blocks or sheets are dried in a current of warm air.
Q12 : You have been gifted a new cell phone which is powered by solar energy.
Write an email to your friend describing the phone and all its exciting features. You may use the notes that you have made in A.7
Answer :
This question is to be answered on the basis of your own understanding, experience and thoughts. It is strongly recommended that you prepare the solution on your own. However, a sample solution has been provided for your reference.
Hey Varun,
I know we meet everyday in gym but I couldn’t wait till then to tell you this. I bought a solar-powered cellphone today. Airbell has launched this product very recently to promote usage of renewable sources of energy. Its widespread popularity lured me into buying this product. Its very easy to recharge this cell as our tropical country experiences bright sunlight almost 10months in a year(although I was upset when it rained the whole day yesterday and the sun was unable to peep in through the clouds.). It is very handy, efficient and appealing to the mass as it uses sun as a charger. So, poor people who don’t have access to electricity find it very economical. It also reduced risks of the danger which radiation poses to our sensory organs.
Lets meet up soon today so that I tell you more about its features.
Take care,
Rajat.