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ELI5 Yahaaa

You would not get stronger

What If Gravity Were Half as Strong?

Your jump would double. Nothing about you would improve.

Now A jump of about halfa metreHalf gravity The same push, twicethe height
The push has not changed. The thing resisting it has.

  1. Step 1 of 5

    Your jump would go exactly twice as high.

    Your jump nowabout 0.5 mYour jump at half gravityabout 1.0 mYour jump on the Moonsix times —about 3 m

    You put the same energy into the same legs, but each metre of height now costs half as much. Nothing about your body improved — the toll got cheaper.

  2. Step 2 of 5

    You would not, however, become stronger.

    Easier Lifting, climbing,carryingExactly as hard Pushing anythingsideways

    This is the part people get wrong. Muscles are unchanged. Anything whose difficulty comes from gravity gets easier — lifting, climbing, carrying. Anything that does not, does not: pushing a car still takes the same shove, because its weight was never the problem.

  3. Step 3 of 5

    Everything falls in slow motion.

    1 Dropped from atable2 Now: about 0.4seconds3 Half gravity:about 0.6seconds
    Films fake low gravity by slowing the tape. That is genuinely what it looks like.

    A dropped cup takes about forty per cent longer to reach the floor. Rain falls more gently, waves break more slowly, and dust that would have settled in seconds hangs in the air for a long time.

  4. Step 4 of 5

    Living things would be built differently.

    Half the gravity, overgenerationsPlants and animals: taller, thinnerHuman bones and hearts: weaker
    Astronauts lose roughly one per cent of hip bone a month, and they train two hours a day.

    Trees could grow far taller before their own weight broke them. Animals could be larger on thinner legs. But human bones and hearts only stay strong because they are worked against gravity — ours would weaken, exactly as astronauts' do.

  5. Step 5 of 5

    And the air would slowly leave.

    Weaker hold onthe atmosphere The fastestmolecules escape

    Air stays because gravity holds it down. Weaken the hold and the fastest-moving molecules at the top escape more easily. It would take an extremely long time — but this is why the Moon and Mars have almost no air, and Earth does.

    Mars has about a third of Earth's gravity and roughly one per cent of its air pressure. The two facts are related.

The short version

Halving gravity halves the toll on every movement, but changes nothing about your strength — and slowly costs the planet its air.

Try it yourself

Watch footage of astronauts on the Moon. They are not moving in slow motion; the film is normal speed. That is what one sixth gravity looks like.

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