# Exercise-6D Heat and Energy Concise Class-9 ICSE Physics Selina Publishers

Exercise-6D Heat and Energy Concise Class-9 ICSE Physics Selina Publishers Solutions Chapter-6 . Step By Step ICSE Selina Concise Solutions of Chapter-6 Heat and Energy  with Exercise-6(A), Exercise-6(B) , Exercise-6(C) and Exercise-6(D) including Numerical and MCQ Questions Solved Visit official Website CISCE for detail information about ICSE Board Class-9.

 Board ICSE Publications Selina Publication Subject Physics Class 9th Chapter-6 Heat and Energy  Exe-6(D) Book Name Concise Topics Solution of Exercise-6(A),  MCQ-6(A)     Exercise-6(C),  MCQ-6(C)   and  Exercise-6(D)   MCQ-6(D) Academic Session 2021-2022

## Exercise-6D Heat and Energy Concise Class-9 ICSE Physics Selina Publishers

–: Select Topics :–

Exercise-6(A),  MCQ-6(A)

Exercise-6(B)  MCQ-6(B),

Exercise-6(C),  MCQ-6(C)

Exercise-6(D),  MCQ-6(D)

Note :-  Before Viewing Selina Concise Physics Solutions of Chapter-6 Heat and Energy for ICSE Class-9 Physics. Read the whole chapter carefully and Solved all example of Chapter-6 Heat and Energy for Class-9 Physics.

### EXE-6(D) Selina Concise Physics Solutions Chapter-6 Heat and Energy

Page 145

#### Question 1

What do you mean by greenhouse effect?

Greenhouse effect is the process of warming of planet’s surface and its lower atmosphere by absorbtion of infrared radiations of longer wavelength emitted out from the surface of planet.

#### Question 2

Name three green house gases.

Carbon-di-oxide, water vapour and methane are greenhouse gases.

#### Question 3

Which of the following solar radiations pass through the atmosphere of Earth ?

X -rays, ultraviolet rays, visible light rays or infrared radiation.

Visible light rays and short infrared radiation pass through the atmosphere of earth.

#### Question 4

What results in the increase of carbon dioxide contents of earth’s atmosphere?

The concentration of carbon-di-oxide content’s of earth’s atmosphere has increased due to industrial growth, combustion of fossil fuels and clearing of forests.

#### Question 5

Name the radiations which are absorbed by the green house gases.

Infrared radiations of long wavelength are absorbed by the green house gases.

#### Question 6  Exercise-6D Heat and Energy Concise

What would have been the temperature of earth’s atmosphere in absence of green house gases in it?

In absence of green house gases, the average temperature on earth would be -18°C.

#### Question 7

State the effect of green house gases on the temperature of earth’s atmosphere.

The greenhouses gases have an average warming effect on Earth’s surface of about 15.5 (or 60 °F ).

#### Question 8

What do you mean by global warming?

Global warming means the increase in average effective temperature near the earth’s surface due to an increase in the amount of green house gases in its atmosphere.

#### Question 9

What causes the rise in atmospheric temperature?

With activities industrialization, deforestation, excess burning of fossil fuel, the concentration of green house gases has increased on earth’s atmosphere. This increase in the amount of greenhouse gases present in atmosphere has caused the rise in atmospheric temperature.

#### Question 10

State the cause of increase of green house effect.

The increase in green house gases due to activities like industrialization, deforestation, natural gas exploration, burning of biomass, natural gas exploration, more use of gadgets like refrigerators has caused the increase of green house effect.

#### Question 11

What will be the effect of global warming at the poles?

At the poles, due to increase in temperature, the snow and ice will melt which will cause flood in coastal countries. The icebergs of dark land and oceans will melt, so the dark land and oceans will become uncovered and will absorb more heat radiations coming from sun, increasing the green house effect further.

#### Question 12

State the effect of global warming in coastal regions.

Due to global warming, the snow and ice around the poles will melt and cause flood in coastal countries.

#### Question 13

How will global warming affect the sea level?

Due to melting of polar ice and glaciers, there will be rise in sea level on coastal wet lands. It would raise worldwise sea level, thereby, many big cities in the coastal areas will be covered by sea water.

#### Question 14

How will global warming affect the agriculture?

Global warming will cause drastic changes in the patterns of wind, rainfall etc. Thus it will result in low agricultural yield.

#### Question 15  Exercise-6D Heat and Energy Concise

State two ways to minimize the impact of global warming.

The two way minimize the global warming are:-

• Use of renewable sources of energy to generate electricity in place of generating electricity from the fossil fuels based power plants.
• Controlling population through family planning, welfare reforms and the empowerment of women.

#### Question 16

What is carbon tax? Who will pay it?

The tax calculated on the basis of carbon emission from industry, number of employee hour and turnover of the factory is called carbon tax.

This tax shall be paid by industries. This will encourage the industries to use the energy efficient techniques.

### MCQ-6(D) Heat and Energy chapter-6 ICSE 9th physics Solutions

Page 146

#### Question 1

The green house gas is :

(a) Oxygen  (b) Nitrogen

(c) Chlorine  (d) Carbon dioxide.

Carbon dioxide

#### Question 2

The increase of carbon dioxide gas in atmosphere will cause :

(a) Decrease in temperature (b) Increase in temperature (c) No change in temperature (d) Nothing can be said

Increase in temperature

#### Question 3

Without green house effect, the average temperature of Earth’s surface would have been:

(a) -18°C

(b) 33°C

(c) 0°C

(d) 15°C

Without green house effect, the average temperature of Earth’s surface would have been -18 °C.

#### Question 4

The global warming has resulted in:

(a) the increase in yield of crops

(b) the decrease in sea levels

(c) the decrease in human deaths

(d) the decrease in sea levels