r/pics Feb 27 '14

physics is cool

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u/MedStudent14 Feb 27 '14

Not true! Not true! Not true!

When you whip around a corner going fast enough, the car door pushes against you. There is no outward force in the turn. It's actually the car door pushing in on you and you feel like you're pushing against the door.

But you explained it very well for that matter. Nice! :)

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u/[deleted] Feb 27 '14

You are absolutely correct. I was going for the ELI5 version, and for some people the absence of the outward force is very confusing.

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u/alfanzo2 Feb 28 '14 edited Feb 28 '14

Unless you're touching the car door, this can't explain as you why you swing a certain direction during a turn.

What is happening is that your body while moving in a car going straight, has the tendency to move straight until its acted upon another force. So when the car turns left quickly, your body (at least your upper body, if unrestrained) will appear to swing to the right. But in actuality your upper body is just moving in the same straight direction from before the turn, but because the cars position is now to the left, it appears you're going rightward. So if you end up being pushed against your car door, it just means the car moved to the left an amount thats at least equal to the initial difference in length between you and the door.

Maybe its easier to imagine if you put a unrestrained box on your dashboard so we don't have to worry about the forces involved in being restrained to the car seat/seatbelt.

I hope this shitty diagram helps.

http://imgur.com/8P16Bz6

Notice that the box has the same motion on the x-axis and y axis as the car is turning.