Test: Movements of Earth- 1 - Class 5 MCQ

- The plane formed by the axis of the Earth and its orbit around the Sun is known as the orbital plane.
- It is an imaginary flat surface that passes through the centre of the Earth and is perpendicular to the axis of rotation.
- This plane defines the path along which the Earth travels in its orbit around the Sun.

Explanation:

-The Earth's axis is tilted at an angle of approximately 66.5 degrees relative to its orbital plane, which is the plane of Earth's orbit around the Sun.
-This tilt is responsible for the seasons as the Earth orbits the Sun.
-However, the angle between the Earth's axis and a perpendicular to the orbital plane (or the ecliptic plane) is 23.5 degrees, making the angle with the orbital plane itself 66.5 degrees.

-The movement of the Earth around the Sun in a fixed path or orbit is called revolution.
-This motion takes approximately 365.25 days to complete, resulting in one Earth year.
-During this revolution, the Earth's axis remains tilted, giving rise to the changing seasons.

Earth has two primary types of motions:

• Rotation: The movement of the Earth on its axis, which causes day and night.
• Revolution: The movement of the Earth around the Sun in a fixed path or orbit, which takes approximately 365.25 days to complete and gives rise to the change of seasons.

Therefore, the Earth has two types of motions: rotation and revolution.

• The term "equinox" refers to the two points in the year when the Sun crosses the celestial equator.
• These points mark the beginning of spring and autumn and are known as the vernal equinox and the autumnal equinox, respectively.
• During an equinox, neither of the poles is tilted towards the Sun. Instead, the Earth's axis is inclined neither away from nor towards the Sun, resulting in approximately equal lengths of day and night around the world.
• This is because the Sun is directly overhead at the equator, and its rays strike the Earth's surface at a right angle, causing equal illumination on both the northern and southern hemispheres.

-On 21st March and September 23rd, the direct rays of the sun fall on the equator.
-These dates are known as equinoxes, and during this time, the plane of Earth's equator aligns with the centre of the Sun, resulting in direct sunlight falling on the equator.
This phenomenon occurs twice a year and marks the beginning of spring in the northern hemisphere and autumn in the southern hemisphere.

• Nicolaus Copernicus, a smart man from Poland, told everyone that the Earth spins around like a top and also moves around the Sun.
• This spinning of the Earth is called rotation.
• When the Earth rotates, the Sun seems to rise in the east and set in the west, giving us day and night.
• So, it's true that Nicolaus Copernicus was the first to say this cool fact about our planet!

• The different seasons on Earth are caused by the tilt of the Earth's axis.
• When the North Pole is tilted towards the Sun, it's summer in the Northern Hemisphere.
• When the South Pole is tilted towards the Sun, it's winter in the Southern Hemisphere.
• This tilt makes some parts of the Earth receive more sunlight and have warmer weather, while others receive less sunlight and have colder weather.

When the North Pole is tilted towards the Sun, the Northern Hemisphere receives more sunlight, leading to summer in that hemisphere. This is because the Sun's rays directly hit that part of the Earth, making it warmer and causing longer days in the Northern Hemisphere.

• The statement is True. The Earth actually takes around 365 and 1/4 days to complete one orbit around the Sun. This extra bit of time is why we have leap years, where we add an extra day to February every four years to keep our calendars in sync with the Earth's movements. So, it's like a little bonus day!
• This extra day in February makes that year a leap year with 366 days instead of the usual 365. So, next time you see February 29th on the calendar, remember it's there to keep our timekeeping all in order!