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  • First, cut a hole in the box...

  • boxxx?

  • weight is a measure of net force the box and scale exert on each other.

    If the chopper was much bigger, it could make the scale read less, but that would happen soon before the chopper lifted the box entirely off the scale.

  • everyone's talking about the Heli weighs X and it takes X+ to lift it. therfore no change in weight .... what if the air was allowed to circulate? what if there were holes in the top of the box (air inlet) and holes on the sides near the bottom (air outlet)? Then the air wouldnt be trapped cancel everything out. I do recognize that air comming in would weigh something but the idea here is that the air is free to travel in and out as opposed to always being contained. whatchya think?

  • Get a lighter box.

  • I'm reminded of a time when I was in primary school, and we had a baloon debate (look it up) and one of the people said they would stand on one leg and weigh less...

    ...And then the teacher aggreed...

    I disputed, and was told to be quiet.

  • what is this witchcraft! lolz

  • I NOW WHY BACUSE THE CHOPPER IS NOT HAVY

  • because the matter never changes mass

  • I saw this one on mythbusters, and me and my dad were mystified. Im not really sure whats going on to do this but my best guess would be the all the air that the helicopter is pushing downward to create thrust is hitting the ground of the box and it cancels out the weight of the helicopter as it isnt touching the ground. So basically if it ways 250 grams then thrust needs to put out 250 grams of thrust, so maybe if it was flown outside and left the box it would be 250 grams lighter

  • its just the thrust from the blades the helicopter need to keep up in the air so the thrust needs to be the same as the helicopter's weight and it adds a little more thrust so it can rise (about more 10-20 so the scale shows a bit more than 10250)

  • Newtons 3rd Law.

    Every Action Has An equal and opposite reaction :p

    Same Story with Pigeons in a trailer lol :)

  • it would only work with helium in the box if you took all the air out and then added helium if you just added helium it would weigh more

  • I understand the consept of why this video was posted, but I'd just use a smaller box. It'd also be safer to ship the chopper in it's original packaging, than to tie it in a large glass box.

  • LOL

  • i'd just put bags of helium in it >_>. but to do that the money cost for bags and the helium might make it worhtless >_>

  • well, tbh, helium is a very cheap gas. silly as it may sound, you're theory might work lol

  • I'd just seal the box and suck the air out

  • the downward thrust it takes to lift a helicopter is equal to its weight to float, and even more to rise. thats the scale shows 10260 and 10270 at different times

  • is like siting in a scale and trying to pull ur self up

  • its the displacement of the air inside of the box

  • its because the helicopter has to push more force down than its weight

  • Good one burningsponge. That downward thrust is definitely the variable. I was really stuck on this one.

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  • There's no difference because the copter is blowing on the bottom of the box.

  • i just want to point out in this video if used for educational purposes that the gram is a measure of mass, not weight. We use it interchangeably in daily language, however weight is actually a measure of gravitational pull on matter. 260 grams of a substance will remain 260 grams even if the weight changes for instance. this scale uses the earths pull to calculate mass, however it would not be accurate for instance on Mars or the Moon.

  • The amount of force to get the chopper off the ground is being pushed down on the box, ergo no weight change.

    You are all nerds. Go out and meet girls. Comic books don't kiss back.

  • If the box is sealed, there is no way its contents could get lighter. Its a closed system. It doesn't matter what movement is going on inside. If the box had an open top, the thrust lifting the helicopter would be equal to the thrust pushing on the ground, and it would still weigh about the same.

  • just use a lighter box, 10Kg for a box is rather a lot. And don't exceed limits or you will get fucked like this.

  • the force need to make the helicopter fly, is the same amount that will be pushed against the bottom of the box. i believe this represents newtons third law...

  • i believe that the torque from helicopters is lateral because the blades cut through the air like a skrew would. but being so close to the bottom of the box, i think your right

  • That sucks his nephew is getting a helicopter without the controller in the box :( .

  • Just a weak ass chopper, lol.

  • For all the people on here coming up with complex explanations, well, why bother?

    The only thing that affects the weight is the total mass of the box and it's contents, and as the box is sealed, this can't change.

    Hence the weight stays the same, no matter what goes on inside the box.

    That's it.

  • your right it was a trick question the helicopter only pushes the wight of the chopper down on the box making no diffrence

  • Bullshit. Fill the box with 260 grams of Helium instead of a 260 gram helicopter and it will actually weigh less.

  • ROFL! Are you actually that mentally defective?

    The weight will be exactly the same.(260 grams of helium in that box would be massively pressurized, and therefore have no 'buoyancy'.)

    You need to learn highschool physics. Oh, and how to think clearly.

  • The critical point properties of Helium are 5.3 K, .23 MPa, and .0578 m^3/kmol (source: Cengel & Boles, Thermodynamics Property Tables Booklet, 2008). So, yeah, pretty compressed. Compression aside, anything that has a mass of 260g and the same volume as the helicopter will have equivalent buoyancy in the surrounding fluid (air) according to Archimedes' principle.

  • I made the assumption in this statement that the weights are equal, which is a pretty safe assumption if the masses are equal and they're on earth. 260g He would, indeed, make the box weigh less if it took up the entire box. But getting rid of the air in the box wasn't mentioned in Snyderman's post.

  • which weighs more? a pound of feathers or a pound of gold.

  • of course a pound of gold, duh :P

  • JaglaJ, they both way the same. They both end up weighing the same thing: one pound.

  • lol, don't you have logic? 260 grams of anything will always weigh 260 grams...

  • dude, sorry to break it to you but the gram is a unit of mass and thusly no matter what you have making up that 260 grams you still have 260 grams of matter being pulled upon by gravity and would then of course result in the same weight under the same gravitational pull. maybe 260 liters or helium would weigh less than 260 liters of helicopter parts, liter is a measure of volume. thought i'd teach rather than make fun of you :)

  • The weight that is being made is from the helicopter flying, and it's attached to the box by strings. I'd just get a smaller box or get rid of the strings on the helicopter.

  • you sir... are dumb

  • The helicopter rises pulling the box up but the wind produced by the rotor is the same weight just changing the weight up summarizing the wind empura the box more than the hanging up of the helicopter

  • put alot of holes at the bottom so the air can escape and the pressure won't show up as much as weight

  • If it was running on petrol it would help :)

  • Heh? Petrol? lol not that it would make a difference you should know piston engines are rather weak.

  • Assuming the elastic bands are for stability, does it weigh the same because the mass of the helicopter is displaced against the mass of the air pushing downwards onto the base of the box transferring the force in Newtons generated by rotor blades? Weight is a force directly proportional to mass. It doesnt matter if the box is filled with liquid or gas as the result is the same. Is that right? I'd rather make an attempt at a guess and sound silly for getting it wrong than make no attempt at all.

  • That sounds right to me

  • woman speak louder

  • to make it weigh less, use a smaller box and don't put a chopper in it?

  • Can he make it weigh any less? Yes use a smaller box!

  • is easy i watch it in mythbuste4rs is because the helicopter fly pushing his weight on air force down soo that waight is still aplied to the box

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  • ☻/

    /▌

    / \

    I just knew that the airforce of that chopper would keep the weight the same

  • just put it in a smaler box

  • it should weigh more. The helicopter has to thrust more than its own weight to fly........

  • It should weight the same. The helicopter has to thrust exactly its own weight to hover. If it thrusted more than its weight it would go up. Since its tied down, thrusting any more than its own weight just goes into lifting the box.

  • the strings pull him down so his thrusting more than needed

  • and it does...10260

  • Why do they speak to the viewer as though they were 5 years old?

  • your forgetting how many trolls are watching this

  • Would work fine if you used a magnet above the box to lift the helicopter.

  • no it wouldn't. Its the same principal. The helicopter would then be hanging from the manget and the extra weight on the magnet would be transfered to the box.

  • Because the chopper is pushing the air against the bottom of the box.

  • pressure

  • Why they never take care of ground effect? They should try with a box with three times the height...

  • The helicopter pushes air down to propel itself upward. The air that is pushed down make the box feel heavier, canceling out the lifting force of the helicopter. Holes in the floor should help. (the scale would have to hold the box from the side

  • hahaha

  • the narrator has a lot of saliva in her mouth. That annoys me.

  • Alternatively, get a larger, lighter box and fill it with hydrogen or helium so it floats. The post office would then theoretically need to pay YOU.

  • its easy, like orgminyak said, every action has a reaction. When the heli was not flying it was pushing with its weight down. The force of the air needed to lift the heli was 250g so the resulting force from the air pushing down was about 250 too

  • innit

  • +20g more force for flying to go higher or if the hellie hoverd it would be 250g i think......=S

  • How about a smaller box...

  • make the box smaller and if it hover it putng down fose makeing it haviary

  • i don't speak welsh,,,

  • for every action there's a reaction. Weight of the chopper was pushing down on the weighing machine. when it lifts up, air is push with thrust as a resultant force but still the total force pushing down on the weighing machine will still be the same - conserved momentum

  • because the heli weighs next to nothing??

  • why not just leave the helicopter in the box it came in as that would only weigh a few grammes. Of course the post office coud still fuck you by putting a 10 Kilo stamp on. then the reiceiver would have to pay the excess. ... poor Jim he has a problem. wheres it going anyway.

  • lol this is like pushing against ur chest, it wont make u move

  • MY BRAIN 'URTS

  • The helicopter's creating air pressure against the floor of the box equal to its own weight. The floor of the box is suspending it as if it were placed directly on that floor.

    Holes in the floor of the box would change the scale reading proportionally to the size of the holes, as now air pressure from the spinning helicopter blades would be created below the box too. Provided there was no lid, or nice big holes in the lid.

  • dude... o.o

    ur gonna be the one im begging for money on the streets :3

  • cut the strings,put a hole in the box so the air pressure is equal to its surroundings refly the chopper.....failing that burn it all and post the carbon

  • for every action there is an equal and opposite reaction...obviously..that's like 6th grade stuff...

  • lol i lerned that about 3 weeks ago and im in yr 10

  • by the way you spell, I would assume you are in "year" 6...

  • haha

  • lol u think ur smarter thn me coz i speak slang well that goes to shows how u jumped to conclusions u twat so i can talk like a year 6 but the end of the day i most probally get a better education dan u

    SOOOOOOOOOOOOZZZZ

  • I bet that's what it is. You can talk all like year 6 but u most probally get a better education. Ill give you a hint, if you can't spell "probably" then you "probably" don't have a better education than I do.

  • PWNED!

  • What? Oh, I'm sorry, I speak ENGLISH.

  • narrrr u dont say... u speak gujaratii -.-

  • because its tied down with strings =] if yu took of the strings and had a smaller box then it would be fine!

  • read up on Newton's laws of motion and post again later.

  • for the helicopter to rise it must push down with a greater force than its weight...

    every action has an equal and opposite reaction.

  • Good call

  • I've thought of a good way to save postage... use a lighter box. Thank you very much.

  • omfg that guys a thicko and he still works at open university... ;)

  • what is wrong with attaching large bags of innert nitrogen or hydrogen to the daft box thus accelerating it voilently upwards! and making postage very cheap for almost nothing?

  • common sense I think, the helicopter has to exert the same amount of force as the weight caused by gravity to get it to atleast hover in the same position so in order to get off the ground the helicopter must create enough thrust against gravity to get higher. This is done by using air and the rotation of the blades to force air below, the air is pushed below the helicopter and onto the surface resulting in the same amount, if not more, force as the original weight of the copter on the box.

  • what about grease? Grease would remove friction and ease movement substantially. Also they could try changing the stupid idiotic soundtrack

  • mass

  • completely inaccurate statements

    the box does not weigh 10Kg

    an objects weight is its mass multiplied by accelaration due to gravity (about 9.8)

    so it weighs about 98N

  • OMG

  • duhhhhhhhhh lol

  • the chopper is in a sealed container so no matter where in the container the atmosphere dus not change and the weight remains the same

  • air is being pshed down on the box from the inside, then down on the scales

  • I think it is because although the Chopper is attempting to suspend itself in the air, thus theoretically lowering the weight of the package as a whole, it is tethered to the box. The string tightens and is exerting the original 250g of weight, carried through the string and distributing itself across the box. In essence, it is because it is still connected to the box. The weight of the box is greater than the Chopper, so will always pull down the 10KG of the box, and the 250g of the Chopper.

  • shhhh no one cares

  • the box does mass 10kg you idiot

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  • The scales are broke :)

  • u idiots are sayin omg it dusn weigh less

    wat he could do is just get a smaller box duh duh i kno its stupid but true get a smaller or a cardbored box

  • basically teh chopper pushes air down

  • Most of the atmosphere is made of Nitrogen which is heavier than oxygen (at a molar scale, not sure of density) but yeah, H2 or He wins.

  • if u're all confused - think of newton's third law

  • the air that the blades push down equalize the weight... i think

  • Shut up all of you!!! now go watch a video of a guy getting his foot choped ok everyone?

  • Forces must be balanced to gain lift? Wow I almost sound clever!

  • the downforce on the box is the same, or greater than the weight of the chopper, as that is what is needed to get it off the ground. Therefore the weight of the chopper is minused, but the downforce of the air is added, canceling each other out.

    A similar question is in the New Scientist magazine's new book; Do Polar Bears get Lonley, only it involved a bridge, and a box of pidgeons lol.

  • yes.

  • what if u poke little holes in the box?

    that way the air pressure wont be held inside and therefore the weight will decrease.

    does this theory mean that if everyone standing on earth took a chopper at the same time then the pressure on earth would be the same as before???

  • Possible, but then people would wonder why the box is sucking in air at the top and pushing it out the bottom. You'd fool a scale the same size as the box. If the scale is bigger than the box, you're still getting the same downward force measured. Everyone in an aircraft would not make the earth weigh but would increase the lower atmospheric pressure slightly, I assume. It would be balanced with lower pressure in the slightly higher atmosphere.

  • If they filled the box with helium, or better still, hydrogen and took the stupid toy chopper out, the box might actually float. Then postage should be really cheap, maybe just $1 or $2 instead of $10.

  • Taking the chopper out of a package consisting of a chopper is not the best idea... but replacing the air (or packing in a vacuum) would lower cost.

  • i just wasted 1:46 seconds of my life watching this!

  • E=mc² according to Einstein so the energy of the helicopter spinning blades generates lots of mass which cancels out their lift - simple

  • I think it's much more simple than that - to lift the helicopter, it must produce lift by forcing air downwards. Because it is in a box, all of that air is then stopped by the bottom, cancelling out the lost weight from the helicopter taking off.

  • Its because of stuff happening in the box and also outside the box - simples!

  • weight is depends on the amount of matter not on the force.... the amount of matter of the helicopter stays the same...... it is still being measured beacause the helicopter is attatched to the box with a piece of string....

  • The reason the box doesn't get any lighter is because any air that the helicopter pushes down to gain lift hits the bottom of the box, thus cancelling out the effect of the helicopter pulling the box up. The only way that this could work would be to but the heicopter outside of the box.

  • maybe buy a lighter box?

  • it is simply because weight is a measure of force not mass

  • the air pushing down from the helicopter needs to be greater than force than the weight of the helicopter itsself for it to lift of the ground, i think ?

  • doesnt it have something to do with thrust/weight ratio or something like that.....basically the heli has to push down more than its own weight to come off the ground...its all to do with equal forces and stuff i think

  • its because the heli isnt properly tied down, if u look at the way the heli is hovering... it seems to keep hitting the surface of the box which creates energy which changes the weight by about 10g. I'm not so sure but i think its called kenetic energy but also the weight doesnt seem to change because everything seems to be contained within itself.

  • is it because the lights are still switched on or wat if you put some eggs in there aswell! would that work

  • explain please

  • because the yoke in the egg acts as a resistance allowing the helicopter to fly up, but i might be thinkin of sausages intstead tho.... also the light can act as a aeromatic balance allowing the chopper to stay airbourne within the box and adding no extra weight...does that explain it a little better?

  • re-try te tes with eggs n sausages in the box ad see if the outcme is any dfferent, remembr the eggs have to less than 8 weeks old an th sausages cannot be froze ; )

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  • Break it up into little bits :P

  • well it was tied down

  • The reason why this happens is because the helicopter needs to make enough downforce to lift its own weight so that would be equal to 250g but it needs even more to get off the ground so it goes up to about 280 then settles to 260 in a hover.

    This is all to do with weight being a measure of force not of mass.

  • Dam you beat me to it

  • smarty pants :)

  • Fill the box with balloons full of helium and it would make the box lighter.

  • defeats the point on paying less.... helium is expensive..

  • There's an episode of "Mythbusters" in the Discovery chanel that shows the same situation.....(Great show, by the way)

  • I know a way of making the weight go down . Just make the chopper fly till it has empty fuel or battery. After the chopper is empty fuel or battery , it is lighter <=

  • because the air is forced down equal to the helicopter duh

  • We can move despite the pressure, which is about 1kg per sq. cm at sea level, ie since 1000 Hectopascal air acts as a ball bearing.

    The atmosphere rests on the surface land and the sea and is 100 km thick, a plane will not add a tiny extra pressure on the ground and any objects that can be found in the atmosphere, as us.

  • By air pressure, it supports aircraft, birds, balloons, clouds, helicopters, airships.

    We do not feel pressure because the exercises to all surfaces of the body and the body is incompressible.

  • you have to be seriously retarded not to figure this out.

  • If you had a sail boat and installed a huge fan to push the sail... Will the boat move?

  • I always wondered that. Maybe I'm stupid in thinking it could

  • yes

  • this will not work simply because it is exerting a force on its own structure

  • what a stupid experiment. you need a bigger box dumbo. large enough that the downward air force can be dispursed and not push on the scale

  • this is due to the helicopters air pushing down on the box every force has an equal and opposite reaction it takes the same power to lift the helicopter as it does to bring it down so the air pushed down equals the helicopters weight

  • no lol. what are you in 6th grade? that definition of newtons 3rd law is a 6th grade def. its because a body of matter cant lift itself up by its own force.try to pick yourself up by your shoe laces you cant because your exerting force on yourself.

  • carlonator3 is kinda right, result of the air pressure from the blast and the gravity acting on the mass of the package. When the helicopter takes off that blast of air from its blades is also pressing down on the scales with a force equal to, if not more than, the weight of the helicopter. So the package as a whole weighs the same (if not a little more).