## Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool

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Any time you drop something,
it falls down.
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But - why? Why do you come back down,
no matter how hard you jump on that trampoline?
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When you throw a ball, why does it fall
to the ground instead of flying off into space?
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The answer is gravity, but it does
a lot more than pulling things down.
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Gravity is an invisible force that
pulls objects towards each other.
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In most cases,
when we say "gravity"
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we are talking about the earth's gravity,
but anything that has mass has gravity, too.
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Yes, even you have gravity!
Of course, you don't have very much gravity.
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The more mass something has,
the more gravitational force it has.
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Compared to the gravity
of the earth,
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any gravitational force that
you have is too weak to notice.
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Mass is not the same
as weight.
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Mass is a measure of the matter in an object,
and does not change no matter where you go.
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On the other hand, weight measures the pull
of gravity on an object, and this can change.
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Most places on earth have roughly
the same amount of gravity,
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but if you were to leave earth,
the pull of its gravity
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would weaken
the farther away you went,
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until eventually
you would experience zero-g.
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This is because gravity
gets weaker with distance.
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There is still gravity in space, because
everything that exists exerts gravitational force,
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but the gravitational pull
from something like a person
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or even a spaceship is so small
it feels as though you have no weight at all.
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If you were to land on another
planet or celestial body,
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the pull of gravity would be
different depending on its mass,
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and you would not weigh
the same as you did on earth.
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On the moon, for example,
gravity is only about 17% of earth's.
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This is because the moon
is much less massive than the earth.
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A person who weighs 100 pounds
or 45 kilograms on earth
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would weigh only 17 pounds
or 7 and a half kilograms on the moon.
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On Mars, the same person
would weigh 38 pounds or 17 kilograms.
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On Jupiter, they would weigh
253 pounds or 106 kilograms.
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Gravity is the weakest of the four
fundamental forces of the universe,
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and only gets weaker with distance,
but it is very important for life on Earth.
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It is the force that holds us down
to the surface of the planet.
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Gravity makes things fall down,
and gives things weight.
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It is what holds the Earth together, and keeps
the air we breathe from spinning off into space.
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Gravity also holds
our solar system together.
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The earth's gravity holds the moon
in orbit around the Earth.
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The sun's gravity holds the Earth and all
the other planets in orbit around the sun.
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On a larger scale, even the Milky Way
galaxy is held together by gravity.
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Scientists believe that a supermassive
black hole sits at the center of the Milky Way,
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with its gravity holding all the gas,
dust, stars and systems in place around it.
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Black holes have so much mass
in such a small space
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that their gravitational pull
is very strong.
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They generate such strong gravity
that not even light can escape from them,
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and that's why
they look black!
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So you see, while gravity
may be an invisible force,
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it has a very visible
impact on our lives.
Title:
Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool
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Video Language:
English
Duration:
04:40
 ALEXANDRE CLEMENTE edited English subtitles for Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool ALEXANDRE CLEMENTE edited English subtitles for Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool ALEXANDRE CLEMENTE edited English subtitles for Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool ALEXANDRE CLEMENTE edited English subtitles for Introduction to Gravity for Children: Gravity, Weight, and Mass for Kids - FreeSchool

# English subtitles

## Revisions Compare revisions

• Edited
ALEXANDRE CLEMENTE
• Edited
ALEXANDRE CLEMENTE
• Edited
ALEXANDRE CLEMENTE