Let's solve each question in the worksheet
"The Solar System" step by step and explain the correct answers.
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1. Which planet is closest to the Sun?
a) Jupiter
b) Mercury
c) Saturn
d) Mars
✔ Correct answer: b) Mercury
Explanation:
Mercury is the smallest and innermost planet in our solar system. It orbits the Sun at an average distance of about 58 million kilometers, making it the closest planet to the Sun.
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2. ________ has a reddish-orange rocky surface
a) Saturn
b) Uranus
c) Venus
d) Mars
✔ Correct answer: d) Mars
Explanation:
Mars is known for its reddish-orange appearance due to iron oxide (rust) on its surface. This gives it the nickname "the Red Planet." It is a rocky terrestrial planet.
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3. The Sun is a _________.
a) comet
b) planet
c) star
d) asteroid
✔ Correct answer: c) star
Explanation:
The Sun is a massive ball of hot gas (mostly hydrogen and helium) that undergoes nuclear fusion in its core, producing light and heat. This defines it as a
star.
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4. The movement of Earth on its axis is called.
a) rotation
b) revolution
c) outer planets
d) none of these
✔ Correct answer: a) rotation
Explanation:
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Rotation is when Earth spins on its own axis, which takes about 24 hours and causes day and night.
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Revolution is the movement of Earth around the Sun, which takes about 365.25 days (one year).
So, the correct term for spinning on its axis is
rotation.
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5. The planets called gas giants are mostly made of.
a) hydrogen
b) helium
c) carbon dioxide
d) both a and b
✔ Correct answer: d) both a and b
Explanation:
The gas giants — Jupiter and Saturn — are primarily composed of
hydrogen and
helium, the two most abundant elements in the universe. These planets have thick atmospheres with no solid surfaces.
(Note: Uranus and Neptune are ice giants, not gas giants, but they also contain hydrogen and helium along with ices.)
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6. Mercury, Venus, Earth, and Mars are called ________.
a) inner planets
b) outer planets
c) far planets
d) near planets
✔ Correct answer: a) inner planets
Explanation:
The
inner planets (also called terrestrial planets) are the four planets closest to the Sun: Mercury, Venus, Earth, and Mars. They are rocky and dense, unlike the outer gas and ice giants.
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✔ Final Answers:
1.
b) Mercury
2.
d) Mars
3.
c) star
4.
a) rotation
5.
d) both a and b
6.
a) inner planets
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Parent Tip: Review the logic above to help your child master the concept of planet worksheets.
