Thursday, June 29, 2023
Tuesday, June 27, 2023
Saturday, June 24, 2023
Dropping a Rock Down an Abandoned Coal Mine Shaft
3 weeks ago
Here's some math for you
The equation for the distance traveled of a free falling object is:
h = v_0t + 1/2(gt^2)
h equals height in meters;
v_0t equals initial velocity in meters per second;
g equals acceleration due to gravity in meters per second squared;
t equals time in seconds.
The initial velocity is 0 since the rock was being held at a standstill by the man. Simplifying the equation we get:
h = 1/2(gt^2)
I watched the video several times and came up with an approximate free fall time of 7.35 seconds. We know that acceleration due to gravity is 9.8 m/s^2. Plugging in the numbers we get:
h = 1/2(9.8 x 7.35^2)
Solving for h we come up with:
h = 264.71 meters
The rock fell approximately 264.71 meters, or about 868.47 feet.
Now that we have a number for distance, we can now see how much the speed of sound affects the equation.
Speed of sound is 343 meters per second
264.71 / 343 = 0.77175
The sound of the rock hitting the bottom was delayed by about 0.77 seconds, which means we need to subtract that time from the original 7.35 seconds.
7.35 - 0.77 = 6.58 seconds of free fall.
Now we have a new free fall time, and can solve for h again with the new number:
h = 1/2(gt^2)
h = 1/2(9.8 x 6.58^2)
h = 212.15
So the rock actually fell about 212.15 meters, or 696.03 feet.
Air resistance would play a role as well, so it may be more like 200 meters or 650 feet, but Ima stop there.
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Friday, June 23, 2023
Thursday, June 22, 2023
Tuesday, June 20, 2023
4 Ways British and American Barbershops Are Very Different
https://www.youtube.com/watch?v=Hd72ms4sYpo
@john2001plus
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0 seconds ago
I only pay about $20 after recent inflation. About a decade ago I was paying $12.
Monday, June 19, 2023
Sunday, June 18, 2023
Saturday, June 17, 2023
Friday, June 16, 2023
So, About This HAIR....
Profound in a small way. Four weeks ago, Hank Greene announced that he had cancer.
Thursday, June 15, 2023
Friday, June 9, 2023
Thursday, June 8, 2023
Wednesday, June 7, 2023
Canadian Tire | Jim Gaffigan
https://www.youtube.com/shorts/RcCnKLy3nwM
I worked from September 1991 to January 1993 for a new business called Auto Source which was a subdivision of Canadian Tire.
"The second time, during the early 1990s, Canadian Tire decided to try to open a specialized auto parts chain called Auto Source that tried to have more than 25,000 different parts on the shelf in each store, more than its competitors. The first Auto Source was opened in Indianapolis in 1991.[25] Unlike the previous attempt, the Auto Source concept was built from scratch.[26] During the next three years, Canadian Tire had opened two Auto Source stores each in Indianapolis, Cincinnati, Dayton, Columbus and Louisville for a total of ten stores before abruptly closing the money-losing chain in 1995.[27][28][29] Some of the stores, were sold to Pep Boys.[30]
Although the Auto Source lost nearly CA$60 million during its four years of existence, a scaled down version was used in Canada under the PartSource brand."
Although the Auto Source lost nearly CA$60 million during its four years of existence, a scaled down version was used in Canada under the PartSource brand."
Sunday, June 4, 2023
Saturday, June 3, 2023
Snake eating itself
https://youtu.be/puKevC5boFg
Perhaps a Darwin Award for a snake.
Maybe hand sanitizer would be a snake repellent.
Best wishes,
John Coffey
Perhaps a Darwin Award for a snake.
Maybe hand sanitizer would be a snake repellent.
Best wishes,
John Coffey
Friday, June 2, 2023
British Thunderstorms Ain't Got Nothing on America
https://www.youtube.com/watch?v=VaxjBYUeff8
I grew up in Indiana and came back to retire. I have been somewhat close to a tornado three times. A town that I lived in just 5 years ago just recently suffered major tornado damage.
Chemo is Weird, Y'all
Been watching this YouTuber, Hank Green, for about 13 years. (The first video I saw is this one: https://www.youtube.com/watch?v=yRRGaxx8Zf4)
A couple of weeks ago he announced that he had lymphoma: https://www.youtube.com/watch?v=x6a4hMyiwBo
He alternates making youtube videos with his brother John, who wrote the book, "The Fault in Our Stars" which was made into a terrific movie. John Green appears in a deleted scene of the movie: https://www.youtube.com/watch?v=PEEQ6-4nKYQ
Thursday, June 1, 2023
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