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A comment on Gravity is not a force – free-fall parabolas are straight lines in spacetime.

Re:Gravity is not a force – free-fall parabolas are straight... by rsp1984 on Monday October 19, 2020 @06:30AM (#24824972)
When standing on Earth we experience a frame of reference that is accelerating upwards, causing objects in free-fall to move along parabolas, as seen in the accelerating frame of reference on the left.

I'm trying to understand what is meant by this. When I drop an item on the floor it goes there in a straight line, not a parabola. Same if I drop something from a helicopter. Obviously I'm missing something here. Can someone with more insight ELI5 this to me please?

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Re:Gravity is not a force – free-fall parabolas are straight... by meditative on Monday October 19, 2020 @06:59AM (#24825125)
it will look like a parabola (or ellipsis if you read elsewhere in this thread) if you add another dimension to your graph of the balls position.

That could be a physical dimension, such as throwing a ball to your friend across the room and plotting x vs y. Or even plotting the height of the ball against time.

https://imgur.com/a/ccBDZf6

consider the x-axis of this image the distance between you and your friend, or time.

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