Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The Solar System consists of the Sun at the center and all the objects that orbit around it, including eight planets, moons, asteroids, and comets.
The Sun is a star, a massive ball of glowing gas that provides the energy (light and heat) necessary for life on Earth.
The eight planets in order of distance from the Sun are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
The Inner Planets (Mercury, Venus, Earth, Mars) are rocky and smaller, while the Outer Planets (Jupiter, Saturn, Uranus, Neptune) are much larger and mostly made of gas and ice.
The Earth rotates on its axis, an imaginary line through its center, once every hours. This rotation causes the cycle of day and night.
The Earth revolves around the Sun in an elliptical orbit. One full revolution takes approximately days, which we define as year.
The Moon is a natural satellite of Earth. It does not produce its own light; it reflects the light from the Sun. It takes about to days to orbit the Earth once.
Gravity is the invisible force that pulls objects toward each other and keeps the planets in orbit around the Sun.
📐Formulae
💡Examples
Problem 1:
If it takes the Earth hours to rotate once, how many hours does it take for the Earth to rotate times?
Solution:
hours
Explanation:
Since one rotation is equal to one day ( hours), we multiply the number of rotations by the hours in a single day.
Problem 2:
Identify the planet that is often called the 'Red Planet' and is the fourth planet from the Sun.
Solution:
Mars
Explanation:
Mars is the fourth planet in the sequence (Mercury, Venus, Earth, Mars) and appears red due to iron oxide (rust) on its surface.
Problem 3:
Why does the Sun appear to move across the sky from East to West during the day?
Solution:
Earth's rotation on its axis from West to East.
Explanation:
The Sun stays in the center of the solar system. It only appears to move because the Earth is spinning at per hour toward the East.