All questions of Motions of the Earth for Class 6 Exam

Explanation:
The time taken by the Earth to complete one revolution around the Sun is known as a year. The Earth rotates on its axis while revolving around the Sun. The time taken by the Earth to complete one rotation is known as a day.

Revolution of Earth:
The Earth revolves around the Sun in an elliptical orbit. The average distance between the Earth and the Sun is about 149.6 million km. The Earth completes one revolution in its orbit around the Sun in 365 days and 6 hours. This 6 hours is compensated for by adding an extra day to the calendar every 4 years. This year is known as a leap year, and it has 366 days.

Importance of Revolution:
The revolution of the Earth around the Sun is responsible for the seasons on Earth. The tilt of the Earth's axis is the reason for the seasons. As the Earth revolves around the Sun, different parts of the Earth receive different amounts of sunlight. This causes the seasons.

Conclusion:
In conclusion, the Earth takes 365 days and 6 hours to complete one revolution around the Sun. This is important because it is responsible for the seasons on Earth. The extra 6 hours are compensated for by adding an extra day to the calendar every 4 years.

1.June or summer solistice( 21st june)

Revolution is the term used to describe the path (or orbit) of Earth through space. Earth's revolution around the sun is responsible for seasonal change and leap years. This path is shaped like an ellipse and has points when Earth is closer to the sun and farther from it.

Some assume our planet's changing distance from the sun causes the change in the seasons. That's logical, but not the case, for Earth. Instead, Earth has seasons because our planet's axis of rotation is tilted at an angle of 23.5 degrees relative to our orbital plane – the plane of Earth's orbit around the sun.

Equinoxes happen two times in a year when day and night are of equal length. ... In the Earth's Northern Hemisphere, for example, the vernal equinox cues the beginning of spring around March 21 and the autumnal equinox indicates the beginning of fall around September 23.

Rotation and Revolution are two motions of the earth. When earth spins or rotates around its axis, that movement of spinning is called Rotation of Earth. And when earth spins or revolves around the sun, that movement is called Revolution of Earth.

Explanation:
The earth travels around the Sun in an elliptical path. This elliptical path is called an orbit, and it takes the earth approximately 365.25 days to complete one orbit around the Sun. The path of the earth is not a perfect circle, but it is slightly flattened at the poles and bulges at the equator. This shape is due to the earth's rotation and the gravitational pull of the Sun and the Moon.

Gravity and the Sun:
Gravity is the force that holds the planets in orbit around the Sun. The Sun's gravity is what keeps the earth and the other planets in our solar system in their respective orbits. The force of gravity decreases as the distance between two objects increases, so the farther away an object is from the Sun, the weaker the force of gravity. This is why the outer planets, such as Neptune and Pluto, take much longer to orbit the Sun than the inner planets, such as Mercury and Venus.

Elliptical Orbit:
An elliptical orbit is a type of orbit in which the orbiting object travels in an elliptical path around the object it is orbiting. In the case of the earth, the elliptical orbit means that the distance between the earth and the Sun varies throughout the year. When the earth is closest to the Sun, it is called perihelion, and when it is farthest from the Sun, it is called aphelion.

Conclusion:
In conclusion, the earth travels around the Sun in an elliptical orbit due to the force of gravity. This elliptical orbit takes approximately 365.25 days to complete, and it is responsible for the changing seasons, the length of the day and night, and other astronomical phenomena.

The correct answer is option 'D': Summer Solstice.

Explanation:

Summer Solstice is the day when the sun reaches its highest position in the sky and appears to stand still for a moment before starting its descent. This day marks the longest day of the year, with the most amount of daylight hours.

The Summer Solstice occurs around June 21st in the Northern Hemisphere and December 21st in the Southern Hemisphere. It is one of the four major events that mark the changing of the seasons, which are known as solstices and equinoxes.

The Summer Solstice is caused by the tilt of the Earth's axis. During the summer months, the Northern Hemisphere is tilted towards the sun, which causes the sun's rays to be more direct and intense. This results in longer daylight hours and warmer temperatures.

On the day of the Summer Solstice, the sun appears to stand still in the sky before starting its descent towards the horizon. This phenomenon is known as the solstice, which comes from the Latin words sol (sun) and sistere (to stand still).

Conclusion:

In conclusion, the correct answer to the question is option 'D': Summer Solstice. This day marks the longest day of the year, with the most amount of daylight hours, and is caused by the tilt of the Earth's axis. Understanding the solstices and equinoxes is important for understanding the changing of the seasons and the patterns of the natural world.

A

The Poles experience about six months of day and six months of night because of the tilt of the Earth on its axis. Because of this tilt, each Pole is tilted towards and away from the Sun for about six months each. When the North Pole is tilted towards the Sun, it experiences continuous daylight for six months.

Circle of Illumination: The imaginary line which divides the parts of the earth with day and night is called the circle of illumination. The circle of illumination is at right angle to the orbital plane. Thus, the circle of illumination is at an angle of 23.5o to the earth's axis.

Option d

This point is distinct from Earth's North Magnetic Pole. The South Pole is the other point where Earth's axis of rotation intersects its surface, in Antarctica. Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes, and 4 seconds with respect to the stars.

February 29 is a date that usually occurs every four years, and is called leap day. This day is added to the calendar in leap years as a corrective measure, because the Earth does not orbit the sun in precisely 365 days. The Gregorian calendar is a modification of the Julian calendar first used by the Romans.

The portion facing the sun experiences day while the other half away from the sun experiences night. The circle that divides the day from night on the globe is called the circle of illumination. ... The earth takes about 24 hours to complete one rotation around its axis.

Winter, Autumn and Spring are names of seasons whereas, Axis is an imaginary line which runs through the poles on which the Earth rotates. 

Direct Rays of the Sun on 22nd December
The direct rays of the sun on 22nd December fall on the Tropic of Capricorn.

Explanation

• Tropic of Capricorn: On 22nd December, the sun is positioned directly over the Tropic of Capricorn. This is because December 22nd marks the winter solstice in the Northern Hemisphere and the summer solstice in the Southern Hemisphere.
• Winter Solstice: In the Northern Hemisphere, the winter solstice occurs when the North Pole is tilted furthest away from the sun, causing the sun's rays to be directly overhead at the Tropic of Capricorn.
• Southern Hemisphere: As the Tropic of Capricorn is located in the Southern Hemisphere, it receives direct sunlight on this day, making it the southernmost point to receive the sun's direct rays.

Therefore, on 22nd December, the Tropic of Capricorn receives direct rays of the sun, while the Tropic of Cancer experiences the winter solstice in the Northern Hemisphere.

Effects of Earth not rotating:

Only half of the earth would experience day and night:
If the Earth did not rotate, one side of the Earth would constantly face the Sun, experiencing continuous daylight. This side would become extremely hot and the other side, which is in continuous darkness, would become extremely cold. The line separating the two sides would experience a perpetual sunrise or sunset.
This scenario would drastically affect life on Earth. Plants and animals rely on the day-night cycle for survival, so the side in constant darkness would face challenges with photosynthesis and regulating body temperature. The side in constant daylight would experience extreme heat, leading to desertification and other environmental issues.
Overall, if the Earth did not rotate, only half of the Earth would experience day and night, while the other half would face extreme conditions that could potentially make life unsustainable.

Angle of Inclination of Earth's Axis
The angle of inclination of the earth's axis with its orbital plane is 23.5 degrees. This angle is also known as the tilt of the earth's axis. This tilt plays a crucial role in determining the changing seasons on Earth.

Significance of the Tilt
- The tilt of the earth's axis causes different parts of the earth to receive varying amounts of sunlight throughout the year.
- This variation in sunlight exposure leads to the changing seasons as different parts of the earth experience different angles of sunlight.

Effects of the Tilt
- The tilt of the earth's axis is the reason behind the summer and winter solstices and the spring and autumn equinoxes.
- During the summer solstice, the Northern Hemisphere is tilted towards the sun, resulting in longer days and warmer temperatures.
- Conversely, during the winter solstice, the Northern Hemisphere is tilted away from the sun, leading to shorter days and colder temperatures.

Conclusion
In conclusion, the angle of inclination of the earth's axis with its orbital plane, which is 23.5 degrees, is a fundamental factor in determining the changing seasons and weather patterns on Earth. Understanding this tilt helps us comprehend the cyclical nature of the seasons and the impact it has on life on our planet.

The Circle of Illumination
The imaginary line that divides day from night on the globe is known as the Circle of Illumination. Here’s a detailed explanation:
Definition
- The Circle of Illumination is an imaginary boundary that separates the illuminated (daylight) side of the Earth from the dark (night) side.
How It Works
- As the Earth rotates on its axis, different parts of the planet experience sunlight while others are in shadow.
- This rotation causes the Circle of Illumination to move, creating a dynamic boundary that constantly changes position.
Why It’s Important
- Understanding the Circle of Illumination helps us comprehend day and night cycles.
- It influences various natural phenomena including weather patterns and animal behaviors.
Other Options Explained
- Equator: This is an imaginary line that divides the Earth into the Northern and Southern Hemispheres, but it does not specifically relate to day and night.
- Prime Meridian: This is the line of longitude defined to be 0 degrees, serving as a reference point for time zones, but it does not separate day from night.
- Axis: This refers to the imaginary line that the Earth rotates around, but it does not create a division between day and night.
Conclusion
In summary, the Circle of Illumination is the correct term for the line that distinguishes the areas of daylight from those in darkness on Earth, making option 'C' the right choice.