00:00five fun physics phenomena number one have a friend hold a cane out horizontally for you or
00:07another similar object and putting your two index fingers together try to place them underneath the
00:12center of mass when they let go you will find it doesn't normally work but now try putting each
00:21index finger at opposite ends of the cane and then moving your index fingers in towards the
00:26middle what you will find is that they always end up right under the center of mass of the cane you
00:35can try starting off asymmetrically and they will still end up under the center of mass you can try
00:44going at different speeds really slowly or really fast but you still end up perfectly under the center
01:01of mass how does this work number two the phone flip have you ever tried to spin your phone if you do it
01:10in this direction it's pretty easy it stays nicely aligned if you spin it along its short axis you'll
01:15also find it spins very well but if you try to flip your phone end over end like this you can't do it
01:22cleanly the phone will never flip simply end over end without also rotating in one of the other
01:28directions even when I make an almost perfect flip instabilities grow until the phone rotates around
01:35another axis why can't no I still can't do it why is it so number three you've probably seen that if you rub a cup on
01:52your hair you can make it electrically charged and if you bring it close to a stream of water you can actually
01:58cause that stream to deflect now usually this is used in chemistry textbooks as a demonstration of the polar nature of the
02:03water water is a molecule with a more positive side and a more negative side and so what happens so you're
02:12told is that the water molecule flips around so the positive side of the water faces the negative side of
02:17the cup and that is what attracts the water to the cup but this is not the real explanation if you have a
02:24uniform electric field there's an equal force pulling the positive side towards it as there is pushing the
02:30negative side away from it and so you can't actually do more than just turn the molecules you would need
02:37a really really strong gradient in your electric field to make this work at all and it basically is
02:42just not going to happen from a cup so why is the stream actually attracted to a charged cup that is the
02:50question number four take a piece of your favorite cereal and drop it into a bowl of water then using a very
02:59strong magnet try to pull the cereal around isn't that cool so why is cereal magnetic and finally five
03:14the tea bag rocket take a tea bag and cut off the sealed end very carefully now dump out the tea
03:23tea form the tea bag into a square column and balance it on the plate now light the top of the tea bag on fire
03:39fire try to light it evenly on all sides get ready for takeoff in three two one ha yeah that is the beauty of the
03:54tea bag rocket so why did that happen so how do all of these phenomena work let me know in the comments or make a
04:05video explaining any or all of them or subscribe to the channel and I'll post the answers next week
04:11I hope you enjoyed those fun physics phenomena I know a guy who would the former commander of the
04:21International Space Station commander Chris Hatfield I'm actually hosting live events with him in late
04:27August in Sydney and Canberra I am so looking forward to that now the Sydney shows are all sold out but
04:32there are still as of now tickets to the Canberra show so if you want to come to that check out the
04:37link in the description now Chris Hatfield actually wrote a book called an astronaut's guide to life on
04:42earth and I am listening to it right now as I travel around the world and it is awesome because it
04:47contains great advice not only for people who want to become astronauts but also for everyone who wants
04:52to lead a meaningful life here on earth and you can download this book for free if you like by going to
04:57audible.com slash Veritasium or you can pick any other book of your choosing for a one month free
05:01trial audible is a great service with over a hundred and fifty thousand titles in all areas of literature
05:06including fiction nonfiction and periodicals and so you can find virtually anything you want there and
05:12by going to audible.com slash Veritasium they know that I sent you and they helped me out to continue
05:18making these videos for you for free so I really want to thank audible for supporting me and I want to thank you for watching
05:27you
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