What is Rotation and Revolution: Definition from CBSE Class 6 Geography

In the Solar System, all the planets perform certain activities to survive. In that, the most fundamental ones are motions under the Sun. Seven more planets can perform these activities in outer space along with the Earth. They are Rotation and Revolution.

In this informative article, the students of CBSE Class 6 will be able to learn all the concepts related to the motions of Earth. Apart from that, they will also be taught all the related concepts in detail.

Rotation – Definition   

A rotation movement is nothing but a circular motion of an element or a substance around a specified centre. Every planet in the Solar System is capable of doing it. They all rotate themselves in an imaginary line. The imaginary line is called a rotational axis. Moreover, if the axis is seen passing through the body’s centre of mass, then the body can be termed as spinning upon itself. 

Revolution – Definition

Often, the word revolution is used interchangeably with the word rotation on many occasions. However, in Geography, both are completely different and are equally important when it comes to outer space.

Revolution is demonstrated as a motion that occurs when one body moves around another. Here, the centre axis can be drawn from the second body. In the Solar System, the Sun is surrounded by eight planets, and all of these planets perform revolution motion around the Sun, using the Sun as the centre axis. Revolution can also be referred to as the orbital revolution in many domains, such as astronomy and related areas.

Earth’s Rotation

In Class 6 Geography, students are taught how Earth rotates and what its causes are. Earth spins around its axis, which is known as Rotation. The axis consists of an angle of 23 12 °. It is seen perpendicular to the plane of the orbit of Earth, which indicates that the Earth is tilted on its axis. Due to this tilt, southern and northern hemispheres are seen leaning in a direction far away from the Sun.

Moreover, because of the Earth’s Rotation, it is divided into two halves, one is bright, and the other is dark. The bright side of the half is because it is facing the Sun, whereas the dark side is not. The bright half gives us a day, while the dark half provides us night. 

The direction of perception decides the order of rotation of Earth. For instance, while viewing down from the North Pole, the spinning of the Earth is anticlockwise. On the other hand, while looking down from the South Pole, the spinning of the Earth is in the clockwise direction.

Benefits of Rotation of the Earth

According to astronomers, there are some benefits due to the Earth’s rotation. They are listed below:

• The cause of tides in seas and the oceans is mainly due to the rotation of Earth.
• The rotation of the Earth determines the cycle of brightness and darkness.

Some day-to-day applications of forces of Rotation

1. Cream Separator: We use this machine while separating or removing the cream from milk. The process of cream separation involves putting the milk into a bowl and spinning it at extreme speeds. Due to the rotation, the heavier content contained in the milk gets forced to move outwards, whereas the lighter contents move towards the centre. Therefore, the denser skimmed milk was collected outside while the more lightweight cream was collected at the centre.
2. Washing machine: The washing machine is a perfect example of rotation motion. When the device is turned on, the basket inside the machine that contains the clothes starts to rotate at high speed, thereby washing the clothes. After several rotations, the water gets thrown out through the holes.

Earth’s Revolution

The CBSE Class 6 Geography students study the Revolution of Earth and its effects on our planet. The Earth’s movement around the Sun is in a fixed circular path. It is referred to as the Revolution of Earth. The Revolution of Earth starts from the West and ends in the East, which indicates that it is in an anticlockwise direction.

Completing one Revolution of the Earth around the Sun takes 365 days, 6 hours and 9 minutes. It is about the stars, and the speed range is between 29.29 and 30.29 km/s. Here, 6 hours and 9 minutes can add one extra day every four years, which we call a leap year. One extra day is added in February as the 29th day of a leap year. Usually, the month of February has only 28 days. 

The given below is some additional information related to the Earth’s orbital Revolution:

• The orbit of the Earth is elliptical. The commencement of the Earth to the Sun is closest on January 4 of every year, with a distance of 147,090,000 km. It is called the perihelion of Earth.
• Meanwhile, aphelion is used when the Earth comes 152,100,000 km away from the Sun. It is six months after the perihelion, during early July.

Rotation & Revolution of Planets

All the planets in the Solar System take a certain amount of time to rotate around their axis and revolve around the Sun. The following data is a tabular representation of how much time each planet takes to rotate and revolve and far they are away from the Sun:

Difference between Rotation & Revolution of the Earth

The Class 6 students need to know about the differences between both the terms. Therefore, below provided is a summary table of Rotation VS Revolution:

Conclusion

For CBSE students, Geography is one of the essential subjects. In Class 6 Geography, a fundamental topic is Rotation and Revolution, which involves the concepts of how the Solar System and all the planets inside it work. 

From this article, the CBSE Class 6 students can understand the concepts of Rotation, Revolution, Rotation of Earth and its benefits, daily life applications of rotational motion, etc. In addition to this, they can also learn how and why the Earth revolves, how Rotation and Revolution differ on other planets and the differences between Rotation and Revolution.

FAQs

1. Is slowing down the Earth’s Rotation possible using artificial techniques?

Human beings make some countable changes in Earth’s rotation period by several microseconds. A greater area of reservoirs has accumulated with trillion tons of water. Furthermore, there is a very common interaction between the weather and this activity in the longer run. It could also affect the strength of the Earth’s magnetic field because it is sensitive to the Rate of Rotation of the Earth.

2. What happens if Earth does not rotate?

The rotational motion of the Earth is about 1000 miles an hour at the Equator. It is considered the fastest moment on Earth. Now, if we assume that the Earth has stopped suddenly for a moment, due to the momentum, all things would fly towards the East at a very high speed. Imagine oceans, rocks, mountains, and houses flying around on top of your heads. It would be extremely scary, and life would suddenly become dangerous. It will also trigger Earthquakes, landscapes, and tsunamis.

3. What are the major effects of Rotation and Revolution?

Rotation of the Earth forces the day to turn into night and night into day. For example, it will be night on Western continents, such as South America and North America. However, on the other side of the world, such as in Australia and Asia.

On the other hand, Revolution is capable of causing seasonal changes such as changing from winter to summer and vice versa. In addition to this, the combination of revolution and rotation causes changes in daily weather, temperature, climatic conditions, wind flow direction, precipitations, ocean currents, etc.

4. What are the effects of Earth’s motions on our life?

Our life is affected by the Rotation of the Earth in many different ways. The main cause of it is the change of day and night. It would have a huge effect on living organisms by forcing them to classify and perform activities based on time. 

Additionally, the Earth’s rotational axis is tilted about 22 to 24 degrees. Due to this tilting action, seasons change every four months.

5. What would happen if there were no existence of Earth’s Revolution?

The Revolution of Earth is very important for us to survive. The effect of the Sun is in every activity in this world. For example, we eat to the weather or climate we experience every day, starting from our food. Therefore, if there is no revolution on Earth, one-half of the Earth will always be cold and frozen, whereas the other half will be dry and hot.

Moreover, it would cause an imbalance in the ozone layer, which in turn will cause global warming. In addition, it would be impossible for either half of the world to survive because one half would never see the Sun, whereas the other would always be in drought.

6. What keeps the Earth rotating?

The Rotation of the Earth is possible due to the presence of an attractive force in the Sun. This force pulls the Earth towards the Sun and pushes it away while revolving. Therefore, it helps create a tangent, which in turn is a rotational force. The rotational force forces the Earth to rotate.