How can a simple apple fall straight down instead of moving sideways?

General relativity

How can a simple apple fall straight down instead of moving sideways?

Imagine you're walking and drop an apple from a tree. Normally, you'd expect it to fall straight down, but sometimes it seems to curve or drift sideways. Why does this happen?

Albert Einstein's idea is that gravity isn't just a force pulling things down; it's actually the space around massive objects like Earth bending. This bending changes the path of objects moving through that space, making them curve towards the object instead of falling straight down.

Example

If you drop an apple from a tree, it falls straight down because Earth's gravity pulls it directly towards the center. But if you drop it near a massive object like a planet, the apple's path curves towards the planet, not just straight down.

Remember this

Einstein's equivalence principle explains that gravity is the result of curved spacetime around massive objects.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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