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Does Water Swirl the Other Way in the Southern Hemisphere?by Prabhav Jain
The idea that water going down a drain or flushed down a toilet swirls in opposite directions in the Northern and Southern Hemispheres has a long history. But few have ever done the experiment. Destin from Smarter Every Day and I performed identical experiments in the Northern and Southern hemispheres. What we found is the direction of water swirl in a toilet, sink, or bathtub is determined by other sources of angular momentum. However if the body of water is big enough, e.g. a kiddy pool, and left still for long enough (at least 24 hours), then the Coriolis effect is observable with water swirling counterclockwise in the Northern hemisphere and clockwise in the Southern hemisphere.
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Water on the Moon?by Prabhav Jain
This Veritasium video inspired me to go and do some more research on the probe that impacted the moon in 2009. Here are some important excerpts I found from the article above on it:
Based on the measurements, the team estimated about 100 kilograms of water in the view of their instruments (the equivalent of about a dozen 2-gallon buckets) in the area of the impact crater (about 66 feet, or 20 meters across) and the ejecta blanket (about 60 to 80 meters across).
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Find the heavy ball puzzleby Matthew Jones
You have 8 balls all of the same size. 7 of them weigh the same, and one of them weighs slightly more. How can you find the ball that is heavier by using a balance and only two weighings?
Solution below divided into hints:
Divide the balls into the following groups: (1,2,3), (4,5,6), and (7,8).
Weigh (1,2,3) against (4,5,6).
Either the two groups are equally heavy. (Case A) One of these groups is heavier than the other. (Case B)
Case A Weigh 7 against 8. Now you have identified the heavier ball in 2 weighing.
Case B Take the heavier group (assume it to be (1,2,3)), take any two balls and weigh them against each other. Either one of these is heavier else the third ball is.
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Request for Videosby Derek A. Muller
I often get a lot of requests for videos so I'll use this discussion to help me understand what you are most interested in.
Reply below with your ideas - if you like someone else's suggestion, simply upvote it so I can see how many people are interested :).
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State of Self Driving Carsby Anant Jain
Inspired by the video on the moral dilemma of self-driving cars, I thought I'd ask the community how they feel about the emerging technology. Given all the work that companies such as Google, Uber, BMW, GM, etc. are putting into it, it's likely the technology will be mainstream the next 5 years. We already have many Tesla drivers using its AutoPilot technology on highways everyday.