I made a trebuchet when I was 13. Saved up for ages to buy the materials and it took ages to construct. On it's first test run my payload (a large rock) amazingly flew directly upwards, came back down and destroyed all my hard work. It was awesome.
I made a marshmallow-throwing trebuchet in physics class my junior year of high school. As it happened, my uncle was in town at the time, and between him, my dad, and me, the design ended up being a chest-high contraption of awesome.
Punkin Chunkin was one of those things that I thought that I wouldn't enjoy, but to my surprise it is now one of the many things that I look forward to when Thanksgiving rolls around.
Energy, as a physics term, refers to the ability to cause change. The simplest form of energy is work, which is force applied over distance. Because of the conservation of energy, all other types of energy can be converted back into work. So a pumpkin with 100 joules of kinetic energy has enough energy to apply a 10 N force for 10 m, or a 1 N force for 100 m, etc. People talk about converting matter into energy, but it's probably more accurate to say that matter is a form of stored energy.
Its some dinner pilgrims and native americans had a long time ago. It became a tradition. We eat turkey dinners and give thanks about stuff. thats it put pretty simply.
I haven't seen one, but I imagine the difference is pretty simple. Fermentation is a specific process in which a fungus eats organic materials and produces a gas (usually carbon dioxide) and an alcohol (usually ethanol) Rotting is a general process in which organic material breaks down in many number of ways, including fermentation but also self-activated cell death (either through running out of energy or burned through some corrosive liquid) and being eaten by small animals and plants.
In 2003, i think, my high school built what was basically a giant pumpkin slingshot and one first in the youth division! Over 900 yards! That was before i went to high school and last year we sold the contraption to help buy a robot for FIRST robotics.
the blue centrifugal, Bad to the Bone, is seriously frightening to behold. They literally clear everyone out from behind it just in case it, yah know...explodes. Cuz that's what it looks like it's gonna do EVERY time.
i is defined by the property i^2=-1, because -i is just as valid a solution to x^2=-1. i^2=-1 is equivalent to i=(-1)^.5, but square roots are inelegant, so we square both sides to get i^2=-1. We also tend to avoid the i=(-1)^.5 definition because that can lead to the false assumption i^2=(-1)^.5*(-1)^.5=(-1*-1)^.5=(1)^.5=1. This false assumption gives a much better reasoning for the existence of i than what I gave earlier. It's much easier to keep track of i than negative square roots.
Not a ton to say about them. They're basically electrons with a positive charge. They're generated during radioactive decay depending on the isotope, and when one meets an electron it results in annihilation of both particles and a release of energy. A positron can join with an antiproton to form antihydrogen.
Were I to join the Punkin' Chunkin' contest, I would be in a new category: Railguns/Coilguns. Place pumpkin in ferromagnetic sabot - build up a helluva lot of electricity in a capacitor bank, release into rails, watch squash fly at mach 17, landing 370 km away (actual figure gotten by the US Navy on one of their test railguns).
Yes I have. I've also formally studied Newtonian mechanics. If you consider the noninertial frame of the rotating ball, centrifugal force appears, clear as day. You have to appreciate the laws of physics as we know them only work for inertial frames (ie constant speed frames). He even admits as such. I'm not arguing that it doesn't exist in the stationary frame of reference, but I AM saying that it exists in some frames of reference.
In high school a couple friends and I decided to build a trebuchet out of boredom. It wasn't nearly on the scale of these, but it did throw a softball well over 100 yards. Not bad for a few goofballs just messing around after school.
It would be an awesome sight if a small army of Punkin Chunkers rolled up on the outskirts of a small town, and started flinging their squishy projectiles at the town centre at the same time :) Could be fun to set up and film in a "ghost town".
YES!! DELAWARE! I LOVE IT WHEN PEOPLE TALK ABOUT US!! Gosh sorry, it's just real exciting to here about your state when people normally forget about you
The worst thing a science education advocate can hear: "but please, don't try this at home...just watch from the safety of your sofa." Hank, you disappoint me.
@2:32 Wrong. since g is constant, and f=ma, only the mass is variable in how much force is applied to the pumpkin. The variable affected by the height of the counterweight is how much time it has to accelerate the pumpkin before it leaves the trebuchet, thus having a higher counterweight affects the velocity of the pumpkin, but not the force applied to it. It is momentum that is force over time, and thus the higher the counterweight and the heavier, the more momentum it gives the pumpkin. DFTBA
I'm happy you pronounced trebuchet like you did. Apparently it's supposed to be pronounced tree-bucket or tré-boo-shet, which make it sound about 10 times less cool.
The only difference between an anti-electron and an electron is that the anti-electron has a positive charge, when normal electrons has a negative charge.
When I was a young alien, I build a pumpkin catapult consisting of a vertical, pumpkin-caliber, nearly-vacuum tube with a pair of teleport gates at the ends, and a switch to connect the bottom gate to a third, 45° upwards pointing ejection gate. The idea was to put the pumpkin into the falling tube, to let it accelerate between the gates, and to turn the switch once it had reached terminal velocity. It was fun! The pumpkin almost reached escape velocity once. I wonder where it went down.
My school used to have a trebuchet competition for the freshman level class, but they replaced it when I was a freshman with a hovercraft competition, which is decidedly less cool than exploding fruits ;P
If we are nitpicking, than centrifugal force is not inertia at the very least because inertia is a scalar and a force is a vector. The point however is that it's not a “real” thing in the sense that there is nothing that exerts that force.
A pumpkin is not a vegetable; it's a fruit! In fact, it's a berry. Pumpkins belong to the family Cucurbitaceae, which includes cucumbers, melons, squash, and gourds.
When discussing the possibility of doing sponsored videos, this one should be held up as an example of how to do it. It feels like it belongs on this channel; it's interesting and well done, like the rest of their work. My main quibble is that I wished the intro or something inside the video itself made it clear that The Science Channel paid for the video, like bloggers have to clearly label sponsored blog posts.
I build a mini trebuchet in "high school" dutch version. it's base was roughly 25 cm high (10 inches) and it could chuck golf balls about 30 meters. incredibly cool to watch lol
I once launched a beef tomato the length of two (British) football fields with a scale model of a trebuchet! It left a pretty mess on teacher's car! Oooppss!
It means, that there are at least 30 people in this world, who imgaine trebuchet, when they hear the word "catapult"! They look just like ordinary people. They might be sitting next to you on the bus, performing a surgery on your grandma or looking after your children, when you're at work. And the worst is, that you'll never know until something happens. I don't know how about you, but this freezes my blood and I'm not sure if I'll be able to feel safe in this world again...
No floating pivot trebuchets? They are more efficient since the weight falls straight down and the arm pivot point moves.... I guess it'd be hard to build a large one.
When dealing with rotating systems it is often useful to use a rotating reference frame. And that includes recognizing all the oddities of a rotating reference frame- most notably the centrifugal and Coriolis forces. And I see people misunderstanding as an opportunity to explain- not to dismiss the topic as non existent.
if the basket or pouch the pumpkin is in is well-done and nicely supports the pumpkin, they can really survive a lot. So far the most extreme machines dont yet really run into such problems. and you could if necessary switch to melons, they are more durable, more dense and more round.
thats why even some universities do their own competitions, students in teams only. also its the only way to learn how to apply your knowledge, building something new from scratch that has to work, so students build race cars and race with them, or micro-sattelites, or all kinds of robots, or flying stuff. Or pumpkin chunkers.
It's definitely not a pointless concept, as usage of non-inertial reference frame can greatly simplify models and calculations. And the point that, I think, people are making when they say that “centrifugal force is not a thing” is to point to non-scientists that their intuition that there is something pulling things outwards is incorrect, but it is not to dismiss the concept all together. I think that MyAJ91 feels the same way in light of his √-1 remark.
That's actually a very poor assumption these days with more and more people moving to UTC as the standard (in the US anyway, it was already a pretty good standard elsewhere). However, in this case we're talking about a US national television provider, so they actually means is 8pm Eastern and Pacific. (The show being repeated in their schedule.)
Hey Hank and other science enthusiasts like myself, I am not only a science lover but I love films and media and creating all those types of things, now I realise that science and films haven't exactly gone hand in hand in the past as films have tended to ignore every rule of physics in the book at some point or another. But my question to everyone and Hank is if you could watch a film based around a science type event or story what would it be??
