Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The Solar System consists of the Sun, eight planets, their moons, and other celestial bodies like asteroids and comets orbiting the Sun.
The Sun is a massive star made of hot gases, primarily Hydrogen () and Helium (), providing light and heat energy.
The eight planets in increasing order of distance from the Sun are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
Earth is called the 'Blue Planet' because approximately of its surface is covered with water ().
Rotation is the spinning of Earth on its own axis from West to East, which takes hours and causes day and night.
Revolution is the movement of Earth around the Sun in a fixed elliptical path called an orbit, taking days to complete.
The Earth's axis is tilted at an angle of , which, along with revolution, causes the change in seasons.
The Moon is the Earth's only natural satellite and takes about days to orbit the Earth.
📐Formulae
💡Examples
Problem 1:
If the Earth takes days for one revolution, how many days are there in a Leap Year?
Solution:
days
Explanation:
The extra day from four consecutive years is added together ( full day) to create an extra day in February every four years.
Problem 2:
Which planet is known as the 'Red Planet' and why?
Solution:
Mars
Explanation:
Mars appears red because its surface is covered in iron oxide (), commonly known as rust.
Problem 3:
Explain why we see different phases of the Moon.
Solution:
Due to the Moon's revolution around Earth.
Explanation:
As the Moon orbits the Earth, different portions of its sunlit side are visible from Earth. One complete cycle of phases takes approximately days.