NCERT Solutions for Class 10 English Chapter 3(A) - Promise for the Future: Renewable Energy

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Chapter 3(A) - Promise for the Future: Renewable Energy Exercise 88

Solution 1

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)

Indian 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

Chapter 3(A) - Promise for the Future: Renewable Energy Exercise 91

Solution 3

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)

Indian 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

Solution 4a

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.

Solution 4b

Not only a renewable and clean source of energy rather it 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.

Solution 4c

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.

Solution 4d

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.

Solution 4e

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.

Chapter 3(A) - Promise for the Future: Renewable Energy Exercise 92

Solution 5

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.

Solution 6

(a) True

(b) False

(c) False

(d) False

(e) False

(f) False

Chapter 3(A) - Promise for the Future: Renewable Energy Exercise 96

Solution 10

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.

Solution 11

Hey Vishal,

I know we meet everyday in gym but I couldn't wait till then to tell you this. I bought a solar-powered cell phone 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. It's 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.

Let's meet up soon today so that I tell you more about its features.

Take care,

Prakash