What Happens to a Helium Balloon in Freefall?

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Hey Everyone! This week’s episode isn’t a full episode, but you should DEFINITELY STILL WATCH because we’re giving t-shirts away to a few of those who can correctly guess the answer to the challenge question. Watch this week’s episode to get your assignment, then get working!

SmarterEveryDay Baffling Balloon Physics

Music:

[Benpurple]

I think I just read all of the comments and no one gave a serious answer. Made me smile

[pbsvoices]

On summer mornings we often wake up and think: "Gosh, if only there were a physics problem to work on. That would really brighten our day". Thank goodness for Space Time.

[MYlifeAScrazy]

Well it's obvious, the minivan won't fall at all because the balloon will make it fly

[PantsuMann]

The answer is that the balloon puts on shades, jumps out of the window with a parachute. The mini van falls to the ground and an massive explosion erupt behind the balloon, which does not look back at the explosion and nice hard rock will be played. The balloon gets all the women.

[NovemberCrystal]

Obviously  the owner is gonna get pissed when he finds out you pushed his minivan off a cliff for some balloon experiement.

[deeperdee]

There wasn't enough information given to accurately calculate the solution. What color was the balloon?

[Kevin-cmkc]

The balloon gains sentience and escapes the van. It then goes on a heartwarming adventure to save Christmas.

[pbsspacetime]

People -- PLEASE DON'T PUT ANSWERS OR THOUGHTS ABOUT THE CHALLENGE IN THE COMMENTS!!! I can't police the comments section all week long, but keep answers to email submissions so all viewers can think about it on their own.  Ok? Thanks, guys. And happy problem-solving! By the way, it's not a race. We'll draw randomly from among the correct answers.
Also, NO QUOTATION MARKS IN SUBJECT LINE. Case/capitalization doesn't matter.

[cortster]

The balloon obviously says, "Fuck this shit" and high tails it out of that van before it plummets to the ground.

[stickyfloor]

It’ll will stay in the same spot and possibly just move around a tiny bit from subtle fluctuations in the air of the van.

[TheEvilVargon]

the balloon would expand and devour the minivan. trust me, im an expert.

[GeneralPublic]

The helium balloon would realize it is in a messed up situation and likely to get popped once the minivan hits the ground, so it would use quantum teleportation to teleport the hell outta there. The minivan would get jealous of the helium balloon and try to teleport after it and the minivan would end up chasing the helium balloon all across the universe in a game of “eternal tag”.

[shahulhusman]

It'll keep the van afloat with the balloons, like in that Pixar movie.. "How to train your Dragon."

[Icarus]

Stumbled upon one of your videos today have have now watched nearly all of them. New favorite channel

[admiralhyperspace]

The ballon stays put, the only reason the balloon rises is because of pressure difference between its bottom and top. And that preasure difference is due to gravity. And the punchline of last video was that a freely falling frame of reference is inertial. Hence no gravity/acceleration. And no pressure gradient to propel the balloon up. So yeah, it falls with the van like it doesn't like to rise up. Just like a ball in free fall.

[MattTheCuber]

Good call taking Destin and his kids out of the car, if you didn't the comments would have blown up. XD

[don_heui]

It will stay at rest because a free falling room is an inertial system. Therefore the air inside the bus and the balloon have no forces pulling them down relative to the bus. Since the air isn't pulled to the floor of the bus as it would with a bus resting on the ground it wont put buoyancy forces on the balloon.

[GetOutsideYourself]

Did they ever post the follow-up video?

[WhiskeyDip]

I really want to be able to discuss this question, it's so tempting

[dhiwakar]

the balloon wil move downward to the floor of the van, because the air move upward due to free fall of the van.hence a low pressure area is created at bottom of the van, where balloon moves,
so balloon wil be at the bottom surface of the van