Yes, I downvote youtube links.

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Cake day: March 8th, 2025

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  • If only we could replace the plane ride before jumping into the sky. I once did the math in my head for how fast you’d have to be shot out of a cannon to reach typical jumping height, and it was a doozy. Disregarding air resistance, it approaches the speed of sound… and since we know how much air resistance matters in skydiving, that method is just out.

    I’m actually curious now. Wingsuits can get a glide ratio of 2-3:1, right? The US census reports average commute time around 26.8 minutes, which (and I’m really spitballing here), might mean an average of 8-20 miles. Even with the wingsuit, that would mean having to get up above 20,000 feet AGL for the shortest distance. Now you’re talking about supersonic cannon speeds, AND are at a height where they start recommending using oxygen bottles.

    Alright, all that was using the idea off getting shot straight up and then gliding from the top. Let’s plug in some horizontal firing. The most efficient horizontal distance is achieved at 45 degrees, not considering air resistance. It looks like you’d be fired at just under 800mph, or 355 meters/second if you like metric, with a horizontal/vertical velocity of 562 mph each. Travel time is about 51ish seconds.

    None of that really makes sense without air resistance though. The fastest speeds for a skydiver just cross 300mph, or 450 ft/sec. The record right now is 527.77km/h, and you cannot deploy the parachute at those speeds without injury or death. So that means our 800 mph initial velocity would have to be far greater so you could get as far as possible before air resistance brings you down to terminal velocity. It also takes time for a parachute to deploy (5-10 seconds), which really throws a spanner in the works for timing. I’d also love to imagine the air traffic patterns as people are willy-nilly shot around metro commuting areas.

    Hmm. I seem to love mixing imperial and metric measurements.







  • When you’re walking alone in the dark all big burly and bearded and just hear a voice calling out sexualizing you it’s scary

    The fear is from the group dynamics more than anything else. Gender almost plays no part in it. Age plays almost no part in it. There are several stories about a group of teens attacking a lone adult, and it goes just about as you’d expect. Anyone who is alone and suddenly becomes the focus of attention by a group will (and probably should) become worried, whereas if you’re in a group the (that is, your) reaction can be anything from ignoring to playing along because you have less to fear. All of us can imagine the difference between walking in a group or by yourself when getting catcalled. Most of us have probably seen the difference.