Eli5 Why can’t we “know” the speed and position of an electron simultaneously? Why can we only measure one of these properties at a time?

Question

This always confuses me and I’m not sure how it works. Please explain…

In: 252

Answer 1

What’s the chance you’ll accidentally move a car if you put measuring tape on it? Zero.

What’s the chance you’ll accidentally move a coin if you put measuring tape on it? Higher than a car.

What’s the chance you’ll accidentally move a human hair if you put measuring tape on it? Almost guaranteed.

Well, with electrons it’s basically the same but even more. Take even one measurement and you certainly disrupted the electron somehow (changed it’s position or speed), so if you take the other measurement, the first one is already invalid by then, hence you can’t know both at the same time.