Basic concepts that seem to escape the grasp of most people

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Nograts

Platinum Member
Dec 1, 2014
2,534
3
0
What's to think about? It's simple math.

1 - 1 = 0. No movement. This ain't no chopper we're talking about here.

If I'm traveling at the speed of light and shoot a gun in the direction I'm traveling how fast does the bullet go?
 

KentState

Diamond Member
Oct 19, 2001
8,397
393
126
People driving expensive luxury cars with bluetooth/handsfree and yet somehow feel more comfortable crooking their head to the side and holding a phone, rendering them unable to properly see their surroundings.
 

Aikouka

Lifer
Nov 27, 2001
30,383
912
126
This is a huge problem in my town:
F-----g idiots that don't tighten-up the space in front of them while stopped at intersections.

The other part of this stupid behavior is when it causes traffic to back-up all the way through another intersection, causing ridiculous congestion. Ignorant assholes have no idea how their actions add-up and severely impact the flow of traffic for everyone.

They do that here too. Here's a fairly extreme example. You can't really see it in the photo, but there's a good bit of room behind that car too. Based on discussions, I find it's because people are huge worrywarts. I had someone tell me, "What if someone hits me from behind?" "How many times has that happened?" "Well... uh... never."

I also see this practically every time I turn left when there are two left turn lanes:

EVERYONE on the outside turn lane moves completely into the inside lane in the middle of the turn and then back into their original lane at the end of the turn. If there are 4-5 cars turning in front of me, every single one of them does it.

I don't see them move into the inside lane completely, but I do see people cut into about half of the inside lane. It's really annoying when I'm in the inside lane, and they can't see me because they're too busy being Dale goddamn Earnheardt! :|

I really ought to just start honking at people more. I like to think of it as a "WTF, Buddy!?". I had to honk at some moran earlier today. I was behind him in the left lane, and all of a sudden, he just drops down 20-30 MPH (on a 65 MPH road) and veers across the right lane and into an interstate on-ramp. I was getting a bit annoyed on the drive home with people driving 35 MPH in a 55 MPH zone. Conditions may not have been absolutely perfect, but the roads being a little damp shouldn't cause someone to react like that. :|
 

CZroe

Lifer
Jun 24, 2001
24,195
857
126
If the plane moves forward 1 m/sec and the treadmill moves back 1 m/sec, the net motion is 0 m/sec. No speed, no lift.

Troll food: "moves forward 1 m/sec"
Think about what you just said. :rolleyes:

What's to think about? It's simple math.

1 - 1 = 0. No movement. This ain't no chopper we're talking about here.
Except that the thrust comes from the propeller or jet and the wheels spin freely. The wheels would simply spin faster and add a small amount of drag/rolling resistance. The plane would continue going forward at almost 1m a second and would take off with enough thrust.
 

Cerpin Taxt

Lifer
Feb 23, 2005
11,940
542
126
Except that the thrust comes from the propeller or jet and the wheels spin freely. The wheels would simply spin faster and add a small amount of drag/rolling resistance. The plane would continue going forward at almost 1m a second and would take off with enough thrust.

Do you even physics, bro?

Say you got a fish that swims at 10 feet/second, and you drop him in a river swimming upstream while the stream rushes down at 5 feet/second.

The fish is only gonna move at 5 feet/second.

Now, if you say that the river is gonna go opposite the fish at exactly the same rate as the fish (i.e. like the treadmill moves under the plane), that fish is gonna be swimming but not moving. Zero speed. If you're a plane, that means no lift.

Go look up what I argued in the last treadmill plane thread. I covered it all there.
 

rsbennett00

Senior member
Jul 13, 2014
962
0
76
Do you even physics, bro?

Say you got a fish that swims at 10 feet/second, and you drop him in a river swimming upstream while the stream rushes down at 5 feet/second.

The fish is only gonna move at 5 feet/second.

Now, if you say that the river is gonna go opposite the fish at exactly the same rate as the fish (i.e. like the treadmill moves under the plane), that fish is gonna be swimming but not moving. Zero speed. If you're a plane, that means no lift.

Go look up what I argued in the last treadmill plane thread. I covered it all there.

In this example, the fish swims in the water, fact. The plane does not drive on the ground, it flies in the air. The wheel speed on the plane has almost zero, as in don't even consider that it's not zero, effect. Planes fly in the air. How does this not make sense to you. Ground speed has no effect on air speed.

Let's copy/paste plane for fish and air for water in your example. Please notice how ground is nowhere in the sentence.

Say you got a plane that flies at 10 feet/second, and you drop him in a sky flying upstream while the air rushes down at 5 feet/second.

The plane is only gonna move at 5 feet/second.

It's ridiculous and that's the point I'm trying to make.
 

Merad

Platinum Member
May 31, 2010
2,586
19
81
Do you even physics, bro?

Say you got a fish that swims at 10 feet/second, and you drop him in a river swimming upstream while the stream rushes down at 5 feet/second.

The fish is only gonna move at 5 feet/second.

Now, if you say that the river is gonna go opposite the fish at exactly the same rate as the fish (i.e. like the treadmill moves under the plane), that fish is gonna be swimming but not moving. Zero speed. If you're a plane, that means no lift.

Go look up what I argued in the last treadmill plane thread. I covered it all there.

Yeah... ball bearings are a thing. You should look them up. Your argument is based around the idea that the wheels on planes work like a car wheel... they don't. Aircraft wheels spin freely.
 

ImpulsE69

Lifer
Jan 8, 2010
14,946
1,077
126
A plane would be standing still regardless of how fast the wheels move, therefore no lift. His fish comparison doesn't work because a fish would still be able to acheive lift in water even if it wasn't moving forward visually due to the water flow moving around it, this would not be happening to a plane and air ; granted if you attribute thrust/pull from propellers/jet engines that is a different story, but it wouldn't be sitting still going same speed; I didn't read the last page or so if someone already pointed that out, but I can't believe this one is still going.
 

Cerpin Taxt

Lifer
Feb 23, 2005
11,940
542
126
Ok it was fun when I was just trolling the aspbrothers, but I don't wanna let it get too outta hand.

Thanks for playing, y'all.
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
A plane would be standing still regardless of how fast the wheels move, therefore no lift. His fish comparison doesn't work because a fish would still be able to acheive lift in water even if it wasn't moving forward visually due to the water flow moving around it, this would not be happening to a plane and air ; granted if you attribute thrust/pull from propellers/jet engines that is a different story, but it wouldn't be sitting still going same speed; I didn't read the last page or so if someone already pointed that out, but I can't believe this one is still going.
Here's a simple analogy that takes care of your misconceptions. Put on a pair of roller blades. Stand on a treadmill going 25mph. Hold on to the handle so you don't go backwards. Now, slowly pull yourself forward. Even if the treadmill was going 100mph, the force to pull yourself forward really wouldn't change much; it's a tiny amount of force. That's what the propeller on the plane does - pulls it forward regardless of how fast the wheels are spinning backwards.

Your misconception/problem is letting go of what propels a car forward. It's not the same thing that makes a plane go forward.
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Here's a simple analogy that takes care of your misconceptions. Put on a pair of roller blades. Stand on a treadmill going 25mph. Hold on to the handle so you don't go backwards.

Ha! You just admitted that a treadmill moves you backwards, even if you're on ball bearings! Therefore, the plane can't take off, QED (I don't know what that means, but I think it's how smart people say "shut up").

:p
 

ImpulsE69

Lifer
Jan 8, 2010
14,946
1,077
126
Here's a simple analogy that takes care of your misconceptions. Put on a pair of roller blades. Stand on a treadmill going 25mph. Hold on to the handle so you don't go backwards.

Oh come on, you know you can't get you tube hits unless you do a header and fly off the treadmill.
 

SlitheryDee

Lifer
Feb 2, 2005
17,252
19
81
Water planes (ones on skiis, which also work on snow), how do they even work? :p

The engine noise scares the invisible fairies tethered in front of the plane. When the fairies try to fly away they pull the plane along behind them. Actually the main reason we haven't moved past combustion engines is because fairies aren't afraid of anything else. Stupid fairies.
 

ImpulsE69

Lifer
Jan 8, 2010
14,946
1,077
126
The engine noise scares the invisible fairies tethered in front of the plane. When the fairies try to fly away they pull the plane along behind them. Actually the main reason we haven't moved past combustion engines is because fairies aren't afraid of anything else. Stupid fairies.

Dammit, all this time I thought it was because water lacks gravity, which is why you float in it. This anti gravity provides lift to the plane.

However this faery thing might explain all the UFO sightings by pilots...