Dick Trauma posted:

Better keep moving when the 'peckers are around...

https://twitter.com/Rainmaker1973/status/1136337927250894848

RareAcumen posted:

https://i.imgur.com/ZbQ0Hzg.mp4

Ariong posted:

ROBOT: INVASIVE_SPECIES_ELIMINATED
ROBOT: ACTIVATE_INVASIVE_SPECIES_SEARCH_PROTOCOL
HUMAN: Wow, great job, Killer! Now activate shutdown protocol so we can get you to the next place that needs you.
HUMAN: Killer? Hello? Activate shutdown protocol.
ROBOT: INVASIVE_SPECIES_LOCATED

Snowglobe of Doom posted:

chitoryu12 posted:

https://i.imgur.com/Ezyqew1.mp4

DontMockMySmock posted:

To maintain a circular trajectory, an object must have an acceleration towards the center of the circle equal to its speed squared divided by the circle's radius (v²/R). If there's too much acceleration, then the car will fall towards the center of the circle (bad news). Let's consider the most dangerous point, the very top of the loop, where gravity points straight towards the center of the circle. There are two sources of acceleration: gravity and the contact force between the car and the track. The contact force can't pull upwards, though, so at the critical threshold where the car barely makes the loop, it will be zero and gravity will be doing all the work. So we can solve the equation g = v²/R, where g is the acceleration due to gravity on Earth's surface (9.8 m/s² or 32 ft/s²) to find the critical speed v where the car barely is going fast enough to make the loop.

Rearranging that equation, we get v = sqrt(g*R).

Estimating based on the video that the loop is about 3 and a half car lengths in diameter, and using a value I googled of 4.5m for the length of a car, we get v = sqrt(9.8 m/s² * 4.5m * 3.5/2) = 8.8 m/s or 19.7 miles per hour.

This doesn't sound like much, and it isn't! In practice, they probably want to be going a fair bit faster for a healthy safety margin. However, they've also got the problem that as they rise through the loop, they lose speed, or in other words, some of their kinetic energy is converted into gravitational potential energy. Assuming that they don't either lose speed to friction or gain speed from their engine during the loop (a bad assumption but the two effects will at least partially cancel out), we can use conservation of energy to figure out how fast they should be going at the bottom of the loop.

KE_before + PE_before = KE_after + PE_after

1/2 m v[sub[before[/sub]² + m g (0) = 1/2 m v[sub[after[/sub]² + m g h

(We can divide through to cancel the masses; the initial height is zero, the final height will be 3.5 car lengths; the speed after will be our 8.8 m/s.)

1/2 v_before² = 1/2 (8.8 m/s)² + (9.8 m/s²)*(3.5*4.5m)

v_before = sqrt[(8.8 m/s)² + 2*(9.8 m/s²)*(3.5*4.5m)]

which comes out to 19.7 m/s or 44.0 miles per hour.

This is all heavily estimated, of course - this is more of an example than a serious analysis of the video. You could get way more accurate measurements if you opened it up in image-editing software and measured pixels and stuff. I did my best to do a quick-and-dirty measure of their speed in the video and I'd say it looks like they were going about 45-55mph at the bottom, which seems like not a lot of margin for error, so probably the circle was a bit smaller than I was estimating, or maybe they get enough of a boost by gunning the engine through the loop itself. Either way, as you can see from these example numbers, it's surprisingly doable. The hardest part is probably getting their insurance company to sign off on this stunt, as if anything goes wrong, you could have someone in a car falling fifty feet, landing with much more force than a car's roll cage is normally meant to handle. So that's probably one good reason why you don't see this stunt done more often - it's surprisingly easy to do, but dangerous as hell.

slothrop posted:

Seems like your red text is pretty prescient.

You mean to tell me that a fiction book, set in "the future", has some historical inaccuracies in order to move the plot along? Shocking!

I don't disagree with the questionable bits, but I'm not going to cancel a novel because it has questionable bits in it.

Here, have a badass picture instead of my ramblings



This is a cobbled together machine used to literally blow out oil well fires.

The Lone Badger posted:

Hopper ants are the ones I hate. They like to climb grass stalks and wait on top to leap onto your legs and sting the gently caress out of you.
They trigger beesting allergies too.

DontMockMySmock posted:

In that video, the Moon's diameter is about 5 times that of the Sun in the sky. This means it is about 1/5 the distance away as it normally is (when its diameter is about the same size as the sun's). A quick check of the wikipedia article on Roche limits says that the moon would have to be within about 18,000 km to experience disintegration, whereas in reality it is 384,000 km. In the video, it would be about 77,000 km, still well outside the Roche limit.

Tidal forces would be about 125 times stronger, as they scale with inverse distance cubed. Off the top of my head, I'm not 100% sure how the increased tidal force exactly translates to the heights of tides on Earth's coasts; my instinct is that they would be simply 125 times higher, which would be the real apocalyptic effect of this thought experiment.

ekuNNN posted:

https://i.imgur.com/A7kRAng.mp4

pik_d posted:

I remember this gif but it was an eagle

https://i.imgur.com/iLUqcjl.mp4

HenryJLittlefinger posted:

It'd be funny if this isn't how it's played at all. I like to think the celts had some kind of rousing jaunty tune played to keep their spirits up.

Also holy poo poo 65,000 people showed up to he a r that thing played.

ekuNNN posted:

"Pipi The Barn Owl (Female, b. July, 2020, located in the Czech Republic). Pipi has a gene mutation called Melanism that is 100,000 to one and is an undue development of dark-colored pigment in the skin or its appendages and is the opposite of albinism."

Field Mousepad posted:

Are antlers the teeth of the forehead? Makes you think

Snowglobe of Doom posted:

https://i.imgur.com/ysJMA6D.mp4

Desert Bus posted:

You see how she's bouncing up and down a lot? It's coming out her rear end.