Today I Learned...
Replies
-
TIL It can take a photon 40,000 years to travel from the core of the sun to the surface, but only 8 minutes to travel the rest of the way to earth.1
-
Coffee is more effective when consumed from 9:30-11:30am1
-
TIL that Airborne drink mix does NOT make you feel better
0 -
You can ask Siri to "Flip a coin".0
-
HealthyAshes88888 wrote: »TIL that Airborne drink mix does NOT make you feel better
Airborne has help me fight off off a couple of colds........1 -
Monkey_Business wrote: »
Airborne has help me fight off off a couple of colds........
Should I keep drinking it then? Lol1 -
Will_Run_4_Food wrote: »
Why is that? The density of the sun or gravity or both? Just a quick question because I haven't really thought it out yet.
The short answer is no one knows what happens. It's all guessing but very good guessing that is much more accurate and usually turns out to be correct. But...
Once a photon of light is born, it travels at a speed of 300,000 km/sec until it collides with a charged particle and is diverted in another direction. Because the density of the sun decreases by tens of thousands of times from its lead-dense core to its tenuous photosphere, the typical distance a photon can travel between charged particles changes from 0.01 cm at the core to 0.3 cm near the surface.
Once you know, or assume, a typical distance between collisions, you also have to figure out how many steps the photon has to take to travel from the core to the surface. This is called the Random Walk Problem. The answer is that, if you take a sequence of N random steps, each for example of one meter length, the distance you travel from the starting point will be the square-root of N. After 100 random steps you will travel about 10 meters, but it will take 10,000 steps to travel 100 meters, and one million steps to travel about one kilometer, and so on. Because the density of the sun changes from the core to the surface, it is common to represent the interior of the sun as a collection of nested shells of matter, each with a typical average density. You then calculate how many steps it takes for a photon to travel through each shell. During each step, the photon travels at the speed of light so you can calculate the time required for each step. By multiplying this by the number of steps taken, you can calculate how long it takes the photon to traverse each shell, and then add up all the times for the other shells.
When this random walk process is applied to the interior of the sun, and an accurate model of the solar interior is used, most answers for the age of sunlight come out to be between 10,000 and 170,000 years.
https://sunearthday.gsfc.nasa.gov/2007/locations/ttt_sunlight.php
5 -
HealthyAshes88888 wrote: »
Should I keep drinking it then? Lol
Yes! I swear that stuff really works. Keep at it...it will at least lessen the severity. Oh and: TIL that not everyone swears by Airborne.2 -
@cee134 Wow! I know about the random steps and approximately the amount of time for a photon to travel from the sun's core.
But with this explanation made me realize is that all of the sunlight hitting the earth at the same time is not all the same age. Mind blown........1 -
HealthyAshes88888 wrote: »
Should I keep drinking it then? Lol
YES!1 -
Thehardmakesitworthit wrote: »
Yes! I swear that stuff really works. Keep at it...it will at least lessen the severity. Oh and: TIL that not everyone swears by Airborne.
Always check your sources.
This was back in 2008:
Maker of Airborne Will Pay Refunds for Product That Was Marketed as a Cold Preventive
https://www.webmd.com/cold-and-flu/news/20080304/cold-remedy-airborne-settles-lawsuit#11 -
This content has been removed.
-
TIL a guy called Vasili Arkhipov saved the world.
Google it.1 -
Always check your sources.
This was back in 2008:
Maker of Airborne Will Pay Refunds for Product That Was Marketed as a Cold Preventive
https://www.webmd.com/cold-and-flu/news/20080304/cold-remedy-airborne-settles-lawsuit#1
Well dang0 -
MeeseeksAndDestroy wrote: »
I make an elderberry syrup that is really good for colds and the flu. Tastes great in tea
My mother was talking about this not too long ago! I'll have to find some
thanks! 0 -
TIL that despite the common misconception, in most countries ship captains are not actually able to perform marriages, and the United States Navy had to make a rule specifically forbidding captains from doing so.1
-
TIL the use of bowls to house goldfish comes from a misunderstanding of Chinese display vessels--small, temporary containers to show guests goldfish that were otherwise housed in ponds. Fishbowls are so detrimental to goldfish health that they are prohibited by places like Rome for animal cruelty.
1 -
You can ask Siri to "Flip a coin".
Do you know how accurate it is?
If the coin is tossed and caught, it has about a 51% chance of landing on the same face it was launched. (If it starts out as heads, there's a 51% chance it will end as heads). If the coin is spun, rather than tossed, it can have a much-larger-than-50% chance of ending with the heavier side down.
However, even on a flat surface it is possible for a coin to land on its edge, with a chance of about 1 in 6000 for an American nickel. Angular momentum typically prevents most coins from landing on their edges unsupported if flipped.1 -
Always check your sources.
This was back in 2008:
Maker of Airborne Will Pay Refunds for Product That Was Marketed as a Cold Preventive
https://www.webmd.com/cold-and-flu/news/20080304/cold-remedy-airborne-settles-lawsuit#1
WebMD..........where everyone has cancer at least once in their life.1 -
TIL that before whistles were introduced, hockey referees used a cowbell. They had to switch to whistles when fans started bringing their own cowbells to disrupt game play.3
-
Dr. George Franklin Grant was a dentist and also an inventor, who patented the wooden golf tee (No. 638,920. Patented Dec. 12, I899). Previously, golfers carried around buckets of sand, placing their balls on little piles as they went.
3 -
This content has been removed.
-
TIL that donkeys look good in wedding hats0
-
MeeseeksAndDestroy wrote: »TIL I learned what "busking" is
same here, just last week I saw a sign that read: Busking Not Permitted1 -
And no wonder. A middle agey, well-to-do acquaintance of mine bragged to a group of us about how his son dropped out of the ivy league (which was all expenses paid) for a year to "busk for a living" while traveling around the U.S. like a hobo. He was so proud. I gagged a little.
this was posted in front of some high faultin' museum, I reckon they had an image to uphold.
I felt fortunate to slip by security....1 -
I don't have to eat ALL the candy in front of me.1
-
TIL there are medical professionals pushing to make sugar a controlled substance. Among other things, they would like to see the FDA remove the "generally regarded as safe" classification of sugar.3
-
TIL that my filter is actually strong AF, who knew?1
-
TIL that if you spent one day on each of the islands in the Phillippines, it would take you almost 21 years to visit them all.
4 -
This content has been removed.
This discussion has been closed.
Categories
- All Categories
- 1.4M Health, Wellness and Goals
- 395.8K Introduce Yourself
- 44.1K Getting Started
- 260.7K Health and Weight Loss
- 176.3K Food and Nutrition
- 47.6K Recipes
- 232.8K Fitness and Exercise
- 448 Sleep, Mindfulness and Overall Wellness
- 6.5K Goal: Maintaining Weight
- 8.6K Goal: Gaining Weight and Body Building
- 153.2K Motivation and Support
- 8.2K Challenges
- 1.3K Debate Club
- 96.4K Chit-Chat
- 2.5K Fun and Games
- 4.3K MyFitnessPal Information
- 16 News and Announcements
- 17 MyFitnessPal Academy
- 1.4K Feature Suggestions and Ideas
- 3K MyFitnessPal Tech Support Questions