scsvshsstclass5e(05.5)

ROTATION AND REVOLUTION (PART 3)

                                  

Welcome back!!

In the previous classes we have learnt about:

• Rotation of the Earth
• How does Earth's rotation cause day and night.

RECAP

Rotation and Revolution are two motions of the earth.

• When earth spins or rotates around its axis, it is called Rotation of the Earth. 

• When earth spins or revolves around the sun, it is called Revolution of the Earth.

In today's class we will learn about ----- REVOLUTION OF THE EARTH

This part of the lesson will teach you to:

*define the term revolution

*explain what causes a leap year

Revolution of Earth

Revolution is the second type of motion of the earth.

The earth revolves around the Sun in a fixed and elliptical orbit. 

This movement of the earth around the sun is called revolution.

For example, Moon revolves around the Earth, and the Earth revolves around the Sun.

The earth takes 365 ¼  days  to complete one revolution around the sun.

A normal calendar consists of only 365 days.

Then, where does the ¼ day or 6 hours go?

Let's learn about this. 

This part of the day or hours is collected for four years till it totals24 hours.

And you know what?

This extra day is added to the February month of every fourth year.

So, this is the reason why February has 29 days instead of 28 days!

• This year with 366 days is called a leap year.

                                    

Leap Year

It takes 365 days and 6 hours (one year) to revolve around the sun. 

This year, 2020, is  a leap year.

               Let's watch this video to know more about the leap year.

Class Work:

Q1 Define revolution of earth?

Ans 1. The earth revolves around the Sun in a fixed and elliptical orbit. 
           This movement of the earth around the sun is called revolution. 
           The earth completes a revolution in about 365 days and 6 hours.

Q2 Why a day is added in a leap year?

Ans 2. The earth completes one revolution in about 365 days and 6 hours.
           The period of 365 days is taken as a calendar year. The 6 hours that are not counted, 
           add up to 24 hours (one day) in 4 years
           This day is added to every 4th year, making it a leap year.

       Complete your work neatly. Which year will be the next leap year?

       Now, I think you can tell, yes!     

            

      That's all for today! 

                             

                                                  Take care😊