Post what's on your mind now

[Tanith]

I'm so happy we get more daylight in the evenings now. If it were up to me, it'd be Daylight Saving Time year-round. None of this sun setting at 4PM bullshit.

[Black Sword]

Tanith seems to have transcended sleep.

WING! Physics time: how much range is added to a weapon like a trebuchet if it's fired from a height? If I remember right, the higher something is launched from, the father it can go due to having farther to fall. Weight of stones is about 100 kg, distance I'd like them to cross is a about a kilometer. Trebuchets had a max range of 300 meters on flat ground back in the day.

Show your work if you want to show off. =p

[carlsojos]

@BS
For the purposes of the math, could you provide the initial velocity and release angle of the projectile?

[Black Sword]

How in the world am I supposed to know that? I'm a general, not a military engineer!

...that was not a suggestion for you to build your own trebuchet, carlos! Put down the 2x4s and nails!

[carlsojos]

I prefer my solid steel ballista catapult, which has enough power to break your kneecaps if you get in the way of the arms during firing. I've actually been pulled over by an ambulance once because I was driving it home from college. The EMT laughed his butt off and took off, lights still flashing. I'll guestimate the velocity based on my experience, and assume a 45 degree launch vector for now.

[Black Sword]

How in the world did you get enough steel to build a solid steel ballista? Especially one big enough to load onto a truck? What's the range on your ballista? 400 meters, give or take?

[carlsojos]

It wasn't that big, it's roughly 5 foot on each axis. Also, I don't own a truck, I drove it home in the back of my Saturn- I basically opened the trunk, used bungie straps to keep it from falling out, and drove home on the interstate. Let me take a picture for you to see, I'll be back in a couple minutes.

[carlsojos]

My cellphone makes a poor camera, but here.


The car next to it is the same one I used to take it home from college- about 60 minutes away at 70MPH. What you can't see is that when we first tensioned the ropes during construction, we broke about 5 welds, and the plate steel on the top and bottom are still bowed in from the force. It takes 3 people to load- one to push each arm back, and one person to set the trigger.

I'll get back to your math problem now.

[Black Sword]

It's not pretty, but I can see it gets the job done. Have you considered adding a crank system to reduce personnel requirements?

[carlsojos]

It would be too much work, given that the trigger has an issue with misfiring and the ropes could use being replaced first. I don't fire it very often, it's mostly just something to launch empty beer bottles at parties, so I don't have an issue with getting a crew together. It's a big hoot, but I hope my friend gets around to building a rail gun like he's been wanting to.

[Black Sword]

That sound you hear is thousand years worth of Roman engineers rolling in their graves because their elegant weapon of death is reduced to firing bottles at parties...

Edit 1: Will a trebuchet stone bounce after its initial landing, or will it dig deep into the earth, causing a tremor?

[carlsojos]

It will usually bounce if the angle at impact isn't too high, however the distance is minute in comparison to the throw itself- it's just extra damage.

Also, I'm a little rusty on my physics, but my math suggests that a trebuchet with a 300 meter range would have to be elevated by roughly 7378 meters to hit a target 1000 meters away- and I didn't account for air resistance, windage, or bouncing/rolling.

Sorry, General Sword.

[Black Sword]

Damn you physics daaaaaaaaaaaaaamn yoooooooooooooooooooooooooooooooooooooooooou.

*gets back to work*

[carlsojos]

Damn you physics daaaaaaaaaaaaaamn yoooooooooooooooooooooooooooooooooooooooooou.

Speed is the biggest factor, in that vertical speed increases while horizontal speed is constant. If you decrease the target range or increase the launch velocity, you might be able to decrease the elevation to a more acceptable level.

I can send you my math if you want to review it.

[Black Sword]

Could you, please? I realized it'd be more than a little helpful in making some adjustments.