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Mark Rober 12 Apr 2025 30 here now

Testing What Happens If You Jump On A Moving Train

Sometimes you gotta go full Tom Cruise to really teach the science. Now go grow your brain even more and get 2 FREE boxes at: https://crunchlabs.com/HotAirBalloon

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Comments (20)

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YESSS now I can see why we can jump in a train and not move but if u jump outside u do! I’ve wondered this abt flys flying in a car!!!! This is abt to educate me
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It's really nice to see your videos. As an engineer you're obviously a decent one to build curiosity and answering them.
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Thank you for explaining Tidal Lock for the moon so simply 👌👍🏼
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Fun fact if you’re flying an airplane and you’re flying into a strong enough headwind, you can go backwards over the ground
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Mark would’ve been the best teacher in the world if he was in high school or even college, but here he is teaching the world. Bro deserves everything and more
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@Jan0990YT From YouTube ↗ 21 Jul 2025 239
14:06 I guess the power went out
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6:47 Entropy have been real silent when this dropped
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wouldve been a cool addition to have an industrial fan blowing at the plane while on the treadmill.
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@bluwhale374 From YouTube ↗ 21 Jul 2025 388
mark: bc the first manmade object to break the speed of sound-
me: celery🗣🗣
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These are some of my favorite videos of yours. Regardless of how simple the science is, I remember when I was younger how much YouTube educators helped me understand science.
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6:38 the pendulums strike back
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@janekrubes From YouTube ↗ 21 Jul 2025 354
14:54 "to understand his answer" but you never let him answer...
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@DroidFAIL From YouTube ↗ 21 Jul 2025 696
A fun demonstration in the same vein as these. If you put a helium balloon in a car with all of the windows closed tight, and then accelerate. The balloon travels towards the front of the car, because the air molecules get pushed to the back of the car, forcing the lighter helium balloon forwards relative to the car.
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This is awesome. Corporate pilot and flight instructor, great explanations on aerodynamics and the changes in atmosphere. I guess the next question is “why is the wind direction different at higher altitudes than lower altitudes?” Might be a perfect introduction to weather theory.
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@RYDENxS From YouTube ↗ 21 Jul 2025 574
I was barely awake when I started the video, but that metronome experiment woke me up and made me really happy. Love being a scientist/engineer
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@gomarky From YouTube ↗ 21 Jul 2025 924
Getting major Myhtbusters flashbacks with a couple parts of this video. Not a knock, more like reminiscing as I see the sync'd pendulum and the plane on the treadmill.
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@Adam-Winrich From YouTube ↗ 21 Jul 2025 4200
That was me cracking the whip!
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I have been watching Mark since I was 12. Now as an engineer myself when I am able to answer his questions before him I really felt I have grown up. Thanks Mark for contributing in developing my engineering brain
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I was a hot air balloon crew chief for a number of years. In addition to the weather reports, we'll also send up our own small helium balloons (piballs) before and during the flight to get a real-time observation of the wind at different altitudes.
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@MarkRober From YouTube ↗ 21 Jul 2025 2100
Sometimes you gotta go full Tom Cruise to really teach the science. Now go grow your brain even more and get 2 FREE boxes at: crunchlabs.com/HotAirBalloon