Class 5 Science | Chapter 1: Gravitation and Earth Pull

Class 5th Science
Chapter 1: Gravitation and Earth Pull

1. Detailed Introduction

Have you ever wondered why an apple falls down from a tree straight to the ground instead of flying up into the sky? Why does a ball thrown up in the air always come back to you? The answer to all these questions is a hidden magical force called Gravitation or Gravity.

Earth Fig 1: Earth Pulling Objects Towards Center
What is Gravitation?
Gravitation is an invisible force of attraction that pulls objects toward each other. Every object in this universe that has mass exerts a gravitational pull on other objects.

The Story of Sir Isaac Newton

A famous scientist named Sir Isaac Newton discovered gravity in the year 1687. He was sitting under an apple tree when he saw an apple drop to the ground. He started thinking deeply about why things always fall downwards. He realized that the Earth must be pulling the apple towards itself with an invisible power. He named this power the 'Earth's Pull' or 'Gravity'.

Why is Earth Pull so Strong?

The rule of gravity is simple: The larger and heavier an object is, the stronger its gravitational pull will be. Since the Earth is extremely massive compared to everything on it (like trees, rocks, buildings, and humans), it pulls everything towards its center. This is why we remain anchored to the ground and do not float off into outer space!

2. Solved Examples (10)

  1. Why does rainwater always fall down towards the ground?
    Answer: Earth's gravitational pull exerts a force on water droplets in the clouds, pulling them down toward the Earth's surface in the form of rain.
  2. Why do we not float in the air like astronauts do in space?
    Answer: The Earth has a massive size and strong gravity that keeps our feet securely locked to the ground. Space has negligible gravity, causing astronauts to float.
  3. If a heavy stone and a light paper ball are dropped together in a vacuum, which will hit first?
    Answer: Gravity acts equally on all objects regardless of weight. In a vacuum (where there is no air resistance), both will reach the ground at the exact same time.
  4. What keeps the Moon continuously orbiting around the Earth?
    Answer: The invisible gravitational pull of the Earth keeps the Moon bound to its orbit, acting like an invisible cosmic thread.
  5. Why do ripe fruits drop down from trees automatically?
    Answer: When the stem becomes weak, the earth's gravitational pull easily tugs the fruit downwards toward the ground.
  6. What happens to a ball thrown horizontally off a cliff?
    Answer: The ball travels forward due to the throw, but gravity simultaneously pulls it down, creating a curved path towards the ground.
  7. Why is it harder to climb up a hill than to come down?
    Answer: While walking up, we work against the direction of Earth's gravity, requiring more energy. While coming down, gravity assists us.
  8. How do tides occur in the oceans?
    Answer: Ocean tides are caused by the gravitational pull of the Moon and Sun pulling the water upward away from Earth's surface.
  9. Does gravity exist on other planets?
    Answer: Yes, every planet has gravity. Planets heavier than Earth (like Jupiter) have stronger gravity, while smaller bodies (like the Moon) have weaker gravity.
  10. What would happen if Earth's gravity suddenly became zero?
    Answer: Everything not attached to the ground—oceans, atmosphere, buildings, cars, and humans—would instantly float away into space.

3. Practice Exercise (15 Questions)

Click on the "Show Answer" button to verify your solution for each question.

Q1. Who discovered the concept of gravitation?

Sir Isaac Newton discovered gravitation.

Q2. Define 'Earth's Pull' in one simple sentence.

The force by which the Earth attracts all physical objects toward its center is called Earth's pull.

Q3. Does an empty box have a gravitational pull?

Yes, every object with mass has gravity, but the box's pull is too tiny to notice.

Q4. What type of force is gravity—contact or non-contact?

Gravity is a non-contact force because it works from a distance without touching the object.

Q5. Why doesn't the atmosphere (air) float away into space?

Earth's gravity holds the gases of the atmosphere close to its surface.

Q6. If you go to the Moon, will your weight increase or decrease?

Your weight will decrease because the Moon's gravitational pull is 6 times weaker than Earth's.

Q7. What keeps the Earth moving around the Sun?

The powerful gravitational pull of the massive Sun keeps the Earth in its orbit.

Q8. Name the fruit that inspired Newton to study gravity.

An Apple.

Q9. Why does a heavy brick fall faster than a feather in real air?

Because air resistance (friction from air) pushes up against the light feather and slows it down.

Q10. In which direction does the Earth's pull act?

It always acts downwards, towards the exact center of the Earth.

Q11. Can we see the gravitational force with our naked eyes?

No, it is an invisible force. We can only experience its effects.

Q12. What happens to the gravitational force between two objects as they move farther apart?

The gravitational force becomes weaker as distance increases.

Q13. Why do rockets need a lot of fuel to launch into space?

They need high energy to break away from the powerful downward pull of Earth's gravity.

Q14. True or False: Your mass changes when you travel to another planet.

False. Mass (amount of matter inside you) remains constant everywhere; only your weight changes.

Q15. Why does water poured from a jug always flow downwards?

Due to the continuous gravitational pull acting on the water molecules.

4. Interactive Science Quiz (15 Questions)

Test your knowledge! Answer all questions and click "Submit Quiz" at the end to get your live score.

1. Gravity is a type of _______ force.

2. Who gave the world the laws of gravitation?

3. Gravity pulls everything towards Earth's _______.

4. If an object is heavier, its gravitational pull will be:

5. Why do we weigh less on the Moon?

6. What would happen to oceans if gravity disappeared?

7. Ocean tides are mostly caused by the pull of the:

8. Which of these items falls slowest in real air due to friction?

9. Gravitational force works across what distance?

10. When you throw a stone up, its speed ________ while going up.

11. The Earth orbits around the ______ due to gravity.

12. An apple falls down because of Earth's _________.

13. Which planet has a stronger gravitational pull than Earth?

14. Gravity keeps us on the ground instead of _______.

15. Gravity is an _______ force.