Gravity and the Solar System Worksheet

Which of the following correctly orders the terms from smallest to largest: galaxy, universe, planet, solar system?

• Planet, solar system, galaxy, universe

• Solar system, planet, galaxy, universe

• Planet, galaxy, solar system, universe

• Universe, galaxy, solar system, planet

Answer explanation

The correct order from smallest to largest is: planet (smallest), solar system (contains planets), galaxy (contains solar systems), and universe (contains galaxies). Thus, the answer is: Planet, solar system, galaxy, universe.

What force keeps the planets in motion around the Sun in our solar system?

• Magnetism

• Gravity

• Electricity

• Friction

Answer explanation

Gravity is the force that attracts planets towards the Sun, keeping them in orbit. It is the dominant force in the solar system, unlike magnetism, electricity, or friction, which do not play a significant role in planetary motion.

Why do planets in other solar systems not revolve around our Sun?

• They are too far away from our Sun

• They are made of different materials

• They are not affected by gravity

• They are invisible to us

Answer explanation

Planets in other solar systems are too far away from our Sun to be influenced by its gravity. Each solar system has its own star, around which its planets revolve, making our Sun irrelevant to them.

Does gravity push or pull? Choose the correct answer.

• Gravity pushes objects away from each other

• Gravity pulls objects toward each other

• Gravity has no effect on objects

• Gravity only affects large objects

Answer explanation

Gravity pulls objects toward each other, which is why we experience weight and why planets orbit stars. The other options incorrectly describe gravity's nature.

Why does the Earth orbit the Sun instead of the Sun orbiting the Earth?

• The Sun is much larger and has more mass than the Earth

• The Earth is larger than the Sun

• The Sun moves faster than the Earth

• The Earth has no gravity

Answer explanation

The Sun is much larger and has more mass than the Earth, which means it exerts a stronger gravitational pull. This gravitational force causes the Earth to orbit the Sun, rather than the other way around.

Which of the following best explains how gravity is related to the motion of the solar system?

• Gravity keeps the planets moving in straight lines

• Gravity keeps the planets in orbit around the Sun

• Gravity only affects the Sun

• Gravity makes the planets spin faster

Answer explanation

Gravity is the force that keeps the planets in orbit around the Sun, preventing them from flying off into space. This gravitational pull is essential for the stable motion of the solar system.

If two planets are the same size, what can you infer about their gravitational pull compared to a much larger planet?

• The two same-sized planets have less gravitational pull than the larger planet

• The two same-sized planets have more gravitational pull than the larger planet

• All planets have the same gravitational pull

• The two same-sized planets have no gravitational pull

Answer explanation

The gravitational pull of a planet depends on its mass. Since the two same-sized planets have less mass than a larger planet, they will have less gravitational pull compared to the larger planet.

What is Pluto?

• An asteroid

• A planet

• A dwarf planet

• It doesn't exist

Answer explanation

Pluto is classified as a dwarf planet because it does not clear its orbit of other debris, which is a key criterion for full planet status. It is not an asteroid or a non-existent entity.

What is the planet ?

• Mars

• Earth

• Pluton

Answer explanation

The question asks for a planet, and among the choices, Earth is the only one that is a planet in our solar system. Mars is also a planet, but the correct answer specified is Earth.

How many planets are there?

• 6

• 7

• 8

• 9

Answer explanation

There are 8 planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The correct answer is 8.