Interesting Facts

[Coult45]

@Administrative

 

[zipper]

On it. Thank you.

 

[FSH 210 Sport]

There is no such thing as cold… just the absence of energy.

Pure water does not conduct electricity

If in a vacuum chamber one was to drop a 5lb weight and a feather, both would drop at the same rate.

 

[buckbuck]

Hmmm...first two make perfect sense to me.
The third one I need to see and understand the science.

 

[FSH 210 Sport]

Hmmm...first two make perfect sense to me.
The third one I need to see and understand the science.

I believe it goes something like this, in a given gravitational field objects of different weights will fall at the same speed, the 5 lb weight has more mass so it accelerates slower than the feather with its lower mass, the feather falls slower in air due to the wind resistances affect on its lower mass. The first experiments that proved this used a ramp and balls of different weights being rolled down the ramp, and they all rolled at the same speed.

This is just one of many very interesting facts I learned from Stephen Hawkins book “A Brief History of Time”. I highly recommend the audio book which is read by Michael Jackson. With Jackson reading, Stephen’s humor and inflection comes through very well.

 

[Matt_D]

Hmmm...first two make perfect sense to me.
The third one I need to see and understand the science.

You're not alone in wanting to see it to believe it. Galileo was the first known to understand how gravity works. But he did his experiments with items that had similar aerodynamic drag. The feather test requires a vacuum.

Apollo 15 Commander David Scott performed this experiment on the moon using a hammer and a falcon feather.

and this video is from the NASA Space Power chamber at NASA Glenn Research Facility in Cleveland Ohio, with feathers and a bowling ball.

 

[Coult45]

Actually, I think every object is acted upon the same by earth's gravity, regardless of its mass. So the 5lb weight and the feather are both pulled down by a force that would accelerate them at 9.8 m/s/s in the absence of any other factors. The force of air resistance is trying to slow them both down, and that's where the mass of the weight gives it the advantage. More mass means more overall force (f=ma) of the falling weight than the falling feather, which overcomes more of the air resistance force. I'm pretty sure Myth Busters did some experiments in a near vacuum to demonstrate, and it's probably on Youtube.

 

[Coult45]

You're not alone in wanting to see it to believe it. Galileo was the first known to understand how gravity works. But he did his experiments with items that had similar aerodynamic drag. The feather test requires a vacuum.

Apollo 15 Commander David Scott performed this experiment on the moon using a hammer and a falcon feather.

and this video is from the NASA Space Power chamber at NASA Glenn Research Facility in Cleveland Ohio, with feathers and a bowling ball.

those are GREAT videos! I was too lazy to search.

 

[buckbuck]

....I need time to process what I just saw....

 

[FSH 210 Sport]

So going back a page in this thread about the blue whales enormous money shot…. When I was dating this gal who had a 15 year old daughter at the time, the daughter had this girl friend who was creepy smart. We were driving to the beach one time in my gf’s four runner with the two girls in the back, and when the ocean came into view the creepy smart girl announced that the ocean was 7% whale sperm…I adjusted the rear view mirror so I could see her and said, excuse me? She confidently stated again that the ocean is 7% whale sperm. I said to her as well as pointing at the ocean, “Do you know how much 7% of that IS ?!!”.

When I got back to work I told my swing shift partner, a math geek, about the above as he was drinking coffee and the coffee shot out of his nose. We then set out trying to figure out how much 7% of the Pacific Ocean is, I can’t remember exactly now what the numbers were but I know that the Pacific Ocean is in the quadrillion of gallons, so you can take 7% of that number and realize that whale sperm quote is crazy. Then we went on to try and figure out how many whales there were based on 7% of quadrillions of seawater being sperm and how many whales there are.…

I’ll see if I can find that paper ….

 

[FSH 210 Sport]

W

....I need time to process what I just saw....

Whats amazing is that this was figured out by people hundreds of years ago without computers or a vacuum chamber.