If gravity stops us floating off into space then why are we able to jump off the ground?
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Gravity is a very weak force.
But…
Gravity is the strongest force in the universe.
How can both be true? Gravity has incredible *range*.
You intuitively know that gravity isn’t that tough, you can overpower the entire planet simply by climbing up a flight of stairs.
But at the top of the stairs fifteen feet away, you haven’t escaped Earth’s gravity. Not even close.
A magnet or an atomic nucleus can project a *much* more powerful force with far less mass, but you can defeat it by moving a foot away.
Gravity has no such range limitations and decreases over a scale of miles instead of millimeters.
You can beat gravity easy for a second, but you’ll never escape its vast range.
Gravity pulls us down. It doesn’t control our position in space directly – we can move around as we please. It instead controls our position indirectly, causing us to accelerate towards the ground.
So if you jump, you can launch yourself up, but the downward force of gravity will slow you down and then send you back down, this ever-present pull towards the ground.
Our muscles are able to push us with enough explosive force against gravity for a short time. Its bassically building muscle. Sure you cant move than 200 pound box of weight but if I gave you 6 months of working out and getting more muscle then you could definetly move the box. When were babys and just learning to walk our leg muscles are weak as we get stronger we can eventually jump a little bit. Because were able to exert over 9.81m/s^2 of force in a short time period
Gravity is a relatively weak force; the jumping strength you have in your legs is stronger than gravity—but you can only jump away from the ground while you’re touching it. Gravity, on the other hand, is a long-range force that can pull you down from far away with no touching required.
**ELI5**
**Think of it like a rubber band.**
You’ve got a rubber band connected to your waist, and the other end is connected to the earth.
You can jump, but unless you jump with enough force to break the rubber band, it’s going to drag you back down.
You could hook your rubber band to a rocket. That’s strong enough to break the rubber band (overcome gravity).
You could go on other planets where gravity is stronger (heavier rubber band). You might not even be able to jump more than an inch here, because that rubber band is far too thick!
You could go to the moon where gravity is far weaker (lighter thinner rubber band). Here you might be able to break the rubber band with a really strong pogo stick or trampoline.
Simply put, because it isn’t a strong force. It’s actually relatively weak, which is why we don’t all just crash into each other and why it takes something like a planet to accumulate a meaningful amount of gravitational pull.
So think of it less like a rigid rope or steel bar and more like a rubber band or bungle cord.
The more force you apply, the stronger the tension between you and the item gets until you reach a point, “snap” the band, and are free. If you don’t snap the band, it pulls you back in once you stop supplying force.
While gravity doesn’t get “stronger” the further you are from the planet, it does accellerate you toward the planet the longer you are not connected to it with your feet. The longer you have to fall, the more accekleration you need to keep accellerating against the opposing accelleration of gravity.
This is why it is usually referred to as a “gravity well.” You can imagine it as a heavy ball on a foam bed. If you roll a marble near the heavy ball, it has a chance to fall into the pit the ball makes in the bed. This is similar to the function if gravity!
This is also why we need a TON of fuel to make it to space. It’s basically an uphill drive the whole way, so it takes a lot if energy to get over the hill and finally be out if the “well.”
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