Long Questions: The Earth in the Solar System | NCERT Summary: UPSC PDF Download

Q1: Torrid zones receive maximum amount of heat, why?
Ans: The Torrid Zone is located between the Tropics of Cancer and Capricorn. On all of the latitudes included in this area, the midday sun is directly overhead once a year. This occurs as a result of the fact that this area receives the most heat. Because the sun's rays fall vertically on this region, the torrid zone receives the most heat throughout the year. It is between the Tropics of Cancer and Capricorn, between 23 1/2N and 23 1/2S.

Q2: Why is having a standard time is necessary? Define IST.
Ans: Indian Standard Time is abbreviated as IST. Every country must have a standard time zone.
The following things will help to understand it:

• Time zones are important when creating a schedule for trains and aircraft. It's difficult to build a time table without a common time because different time zones have different times.
• Standard time also aids in maintaining time consistency across the country.
• The standard meridian is located at a longitude of 82°30'E and is known as IST (Indian Standard Time). This meridian is used to calculate India's standard time.

Q3: What is the Meridian that is taken as the standard time of India?
Ans: In India, 82° 30' E is regarded as a standard meridian because the time difference between 1° longitude and 82° 30' E is 4 minutes.
The whole longitudinal space of India is 30 degrees (97°E-67°E=30°E). As a result of the total time difference of 30X4=120 minutes or 2 hours, the time difference between Gujarat and Arunachal Pradesh is 2 hours.
We chose a standard meridian to avoid such confusion and to ensure that everyone in the country is on the same time.

Q4: Describe The Sun and its planets with the help of a diagram.
Ans: The Sun:

• The Sun is at the centre of the Solar System. It is the head of the Solar Family.
• It is made up of extremely hot gases.
• The Sun provides the gravitational pull that binds the Solar System.
• It is also a massive store house of energy. The energy is essential for life on the Earth.
• The Sun is about 15 crore km away from the Earth.

Planets:

• There are eight planets in the Solar Family.
• In order of their distance from the Sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
• Mercury is the nearest to the Sun, while Neptune is the farthest from the Sun.

Q5: Explain some features of the earth.
Ans:

• The Sun has heat and light which makes life possible on the Earth.
• The Earth is slightly flattened at the poles, and has a bulge on equator. Its shape is Geoid.
• Conditions favourable for life are found on the earth.
• The Earth is also called the blue planet as from the sky it looks blue because of the presence of water on it.
• Our Earth has only one natural satellite. It is called the Moon.

Q6: Explain about the three heat zones of the earth.
Ans: The earth's three heat zones are:

• Torrid Zone: The Torrid Zone is the region between the Tropics of Cancer and Capricorn that receives the highest heat.
• Temperate Zone: This is the area in the northern hemisphere between the Tropic of Cancer and the Arctic Circle, and in the southern hemisphere between the Antarctic Circle and the Tropic of Capricorn. The temperature is moderate.
• Frigid Zone: This part of the world is quite chilly. In the northern hemisphere, this is the area between the Arctic Circle and the North Pole, while in the southern hemisphere, it is the area between the Antarctic Circle and the South Pole.

Q7: What are the meridians of longitude and parallels of latitude?
Ans: The imaginary line that separates the planet into the Northern and Southern Hemispheres is known as the Equator. By 0 degrees latitude, the equator is represented. The North Pole is located at 90° north latitude, whereas the South Pole is located at 90° south latitude. The world is divided into equal halves by this circular line. From the equator to the poles, there are parallel circles. The measurement units for latitudes are degrees.

Q8: Describe asteroids and meteoroids.
Ans: Asteroids:

• Besides Stars, Planets and Satellites there are also numerous tiny heavenly bodies.
• They also revolve round the Sun.
• They are called asteroids.
• They are found between the orbits of Mars and Jupiter.
• The largest asteroid is Ceres.
• Asteroids are parts of a planet which exploded many years back.

Meteoroids:

• The small pieces of rocks which revolve round the Sun are called meteoroids.
• When they enter the earth’s atmosphere, they begin to burn.
• These burning rocks are called meteors.
• They cause a flash or sink of light.
• A meteor not destroyed fully, falls on the earth. It is called a meteorite. It creates a hollow or depression in the ground.
• A very good example of such a meteorite depression is in Arizona, USA. India has an example of such depression in Ramgarh in Rajasthan.

Q9: Differentiate between a Planet and a Satellite.
Ans:

Q10: Distinguish between a Satellite and a Star.
Ans:

Q11: Why can the earth not be compared to other planets of the Solar System?
Ans: The earth cannot be compared to other planets of the Solar System because of the following reasons:

• It is only the earth which has life on it.

Conditions favourable to support life are found only on the Earth:

• The Earth is neither too hot nor too cold.
• It is the only planet which has water on it. Water is very essential for our survival.
• It has life giving gas, oxygen.
• It also contains ozone layer, which protects us from harmful solar rays.

Due to these reasons the earth is a Unique Planet in the Solar System.