Air loop tunnels

Removing the air (vacuum) is a good solution for super sonic speeds. But what about moving sea level density air through the tunnel at sub sonic speeds such as 100s of meters per second? That way you can ride through the tunnel at say 200 meters/sec (~450 mph) with the top down without having your hat blow off thanks to a constant strong tailwind going roughly same speed as the vehicle. No need for pressurized cabins!

The moving air would also help propel the vehicle forward a bit. A light vehicle with a sail could possibly be propelled solely by the wind! The air could also whisk away heat generated by the magnetic propulsion system.

Maybe the air system could be in a loop, more efficient than sucking it in and blowing it out to the atmosphere. Maintaining airspeed shouldn't be a problem, not much air resistance to overcome.

https://en.wikipedia.org/wiki/Pneumatic_tube

Interesting facts about Seasons

Distance to the Sun
-Northern hemisphere Winter: Earth is closest to the Sun
-Northern hemisphere Summer: Earth is farthest from the Sun

Length of day
Days are longer during the Winter than in the Summer. I don't mean 'daylight hours', yes those are shorter during the Winter, I mean the time from Noon to Noon.

The Earth spins around it's own axis at the same rate all year around, however, the Earth orbits faster when it's nearer to the Sun, hence it takes longer for the Sun to return to the highest point in the sky. When viewed from above the Earth spins CCW and orbits CCW.

Because of this the Sun actually travels angularly faster across the sky in the Summer, but stays up longer because it travels along a longer arc than in the Winter.

Area facing the Sun is a major factor in Solar energy collection (and Seasons.)

I measured the power collected from a small solar panel.

When always facing the Sun:

-When the Sun is straight up 5 watts was collected.

-When the Sun is 60deg from zenith 4 watts was collected.

Not a huge difference from 0 to 60deg.

However if I tilt the small solar panel even when the Sun is straight up the power is greatly affected. Tilted so much that the area facing the Sun is halved, the power halved as well. (power breakdown: voltage remained around 24v, it's the current that changed.)

Same deal with the north and south hemispheres.

-In the Summer time more north hemisphere area faces the Sun.

-In the Winter time less north hemisphere area faces the Sun.

Not quite the extreme altitude of the Sun, but same principal in these examples:

Baja California takes up alot of screen space (so greater solid angle) during the Summer
https://earth.google.com/web/@22.01938439,-113.02998305,-2425.40930916a,12568971.6672492d,35y,0.17716338h,8.68143677t,-0r

Baja California takes up very little screen space (so less solid angle) during the Winter
https://earth.google.com/web/@-22.01938439,-113.02998305,-2425.40930916a,12568971.6672492d,35y,0.17716338h,8.68143677t,-0r

https://en.wikipedia.org/wiki/Solid_angle

A yelling language

Let's face it, you can't yell consonants. Hence words that are only differentiated by consonants will be easily confused with each other when you need to yell.

There are probably many better examples, but here are a few I can think of off the top of my head

code, mode

call, tall

lame, tame

A proper yelling language should consist of only vowels, or sounds that you can sustain. I think radio transmissions can be a good guide: variations of amplitude and frequency.  https://en.wikipedia.org/wiki/Yodeling probably utilizes these ideas, and could become a long distance language.

Cameras or mirrors in the front of vehicles

Notice that when exiting this parking lot just to see cars coming down the road half of your vehicle has to stick halfway out into the lane due to not being able to see through the parked cars! (posted speed limit is 30mph, but vehicles typically travel faster than that.)

https://www.google.com/maps/@32.8698966,-117.233749,3a,89.9y,137.32h,54.45t/data=!3m6!1e1!3m4!1syTOgwwzuE8VnmnDWT9kZXQ!2e0!7i13312!8i6656

This is because people's eyes are in the middle of the vehicle. One solution would be to have mirrors or cameras on the front of the vehicle. Or having a mirror in the middle road island. Or being to access nearby cameras mounted on say light posts.

Designing containers for smooth pouring

I'm sure many have noticed that when pouring liquid bottles it comes out in big clumpy waves. One wouldn't need a funnel if they'd design these things with proper airflow in mind to fill up space vacated by the liquid. Either use larger diameter spouts, or have another spout for air intake while liquid pours (as seen in a few liquid detergent bottles.)

Layers of tunnels to add traffic lanes

After the https://en.wikipedia.org/wiki/Interstate_Highway_System little has been done to significantly improve traffic flow. The populations have ballooned while road lanes have not.

Many places were designed street widths for a certain amount of traffic. The streets are now adjacent building locked so they can no longer widen them to accommodate the massive amount of traffic during the rush hour.

Since lateral road expansion isn't possible without razing buildings, we are left with vertical expansion. Going up with say double decker roads would be unsightly, no one would go for that. This leaves underground tunnels as the only real solution for adding more lanes. Only so many opt for mass transit such as buses and trolleys, many want the freedom and flexibility that automobiles afford

So much talk about housing crisis with little mention of the associated traffic crisis. People also need more lanes not just more houses. Less time on roads means more time to be productive. I suppose self driving cars will make waiting in traffic more bearable in the mean time as you'll then be able to do many of the things you'd do when you got home, such as check email.

Slightly north is the quickest way south

Ever wonder why the Sun sometimes appears to the north of your location even though the sub solar point https://en.wikipedia.org/wiki/Subsolar_point is at a lower latitude from your location? One must remember that the initial direction is just that; initial. A straight line on the globe follows a great circle https://en.wikipedia.org/wiki/Great_circle . Unless that great circle follows a line of longitude or the Equator, the path direction along each point of that great circle changes. Great circles are basically the same as https://en.wikipedia.org/wiki/Orbital_inclination where if you keep going it bounces between a northern and southern latitude line.

4.9 mega meter distance example
Cabo San Lucas: +22.9 lat -109.9 lon
Honolulu: +21.3lat -157.8lon

A straight line path from Cabo has an initial heading of 277.6 deg (7.6 deg north of west) even though Honolulu is at a lower latitude (1.6 deg lower.) The great circle path will actually reach up to +24.0 deg latitude along the way.

13.0 mega meter distance example
Cabo San Lucas: +22.9 lat -109.9 lon
Manila: +14.6 lat +121.0 long

A straight line path from Cabo has an initial heading of 302.0 deg (32 deg north of west) even though Manila is at a lower latitude (8.3 deg lower.) The great circle path will actually reach up to +38.6 deg latitude along the way.

20 mega meters is halfway around the Earth.