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Confused about circular motion

I'm really not understanding something here.

I've read and watched many videos but something's not clicking.

If I swing a bucket around in a vertical circular path fast enough so the water doesn't fall out at any point, then why doesn't the water fall out the bucket at its greatest vertical height (right above my head) despite the fact that centripetal acceleration is directed towards the centre (downwards)? The water supposedly experiences centrifugal force but that doesn't exist so I'm confused as to why the water doesn't fall out when it experiences both a normal reaction force from the bucket and centripetal force.

Reply 1

RogerOxon

Original post by BTAnonymous

If I swing a bucket around in a vertical circular path fast enough so the water doesn't fall out at any point, then why doesn't the water fall out the bucket at its greatest vertical height (right above my head) despite the fact that centripetal acceleration is directed towards the centre (downwards)? The water supposedly experiences centrifugal force but that doesn't exist so I'm confused as to why the water doesn't fall out when it experiences both a normal reaction force from the bucket and centripetal force.

The water does fall, but so does the bucket as it goes around the circle. If it weren't going around the circle quickly enough, then it would fall faster than required to go around the top of the circle.

Reply 2

BTAnonymous

Original post by RogerOxon

So what about if I was standing inside the circumference of a circular wheel which rotates sufficiently enough for me to stand 'upright' in my point of view? Same principle?

Reply 3

RogerOxon

Original post by BTAnonymous

So what about if I was standing inside the circumference of a circular wheel which rotates sufficiently enough for me to stand 'upright' in my point of view? Same principle?

Yes.

At the top of the circle, you are falling, but you're also moving horizontally. It's just a question of whether you're falling faster than required for the circular motion or not.

Reply 4

Physics Enemy

Original post by BTAnonymous

...

Mathematically in such cases e.g) top of a looping rollercoaster: N + mg = mv^2/r => N = m(v^2/r - g).

To stay in contact (not fall) N > 0, so v > Sqrt(g/r). Smaller the circle, faster you/object must travel.