Curious Kidsis a series for children of all ages.
If you have a question youd like an expert to answer, send it tocuriouskidsus@theconversation.com.
Why does gravity pull us down and not up?
It is why apples fall toward the ground and planets orbit stars.
Magnets attract some types of metals, but they can also push other magnets away.
So how come you feel only the pull of gravity?
In the movie ‘Interstellar,’ the characters go to a planet close to a black hole, and while they are there, they age slower than everyone else.
In 1915, Albert Einstein figured out the answer when he published histheory of general relativity.
That curvature is what you feel as gravity.
What is spacetime?
It’s free, every week, in your inbox.
Before getting into the complicated world of gravity, you oughta understand spacetime.
Earth curves spacetime so that you fall toward Earth instead of away from it.
This is a two-dimensional example of how spacetime works.
Your mass stretched the trampoline, creating what is called a gravity well that the ball rolls into.
So to make it easier to visualize, imagine the surface of a trampoline.
If there is nothing on it, it is flat.
If there is a ball on the trampoline, it would roll toward your feet.
The heavier you are, the steeper the sides of the trampoline well.
So why does gravity pull you down and not push you away?
Imagine someone went under the trampoline and pushed up.
The ball would roll away!
This would be a gravity hill, not a gravity well.
As far as scientists know, matter or stuff always makes gravity wells and not gravity hills.
Hello, curious kids!
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kindly tell us your name, age and the city where you live.
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