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  • If you wake up one morning

  • with 1,000 times the strength you had the night before,

  • how will you handle delicate day-to-day tasks?

  • Everything must seem so fragile to you

  • since the scale of your strength

  • has expanded one thousand times.

  • You'd have to be very careful

  • when you're shaking someone's hand

  • so you don't end up breaking their bones

  • or crushing everyone you hug.

  • And using a fork to pick up a piece of broccoli

  • from a Styrofoam plate

  • without driving the fork through the plate

  • is going to be as difficult as brain surgery.

  • Say the day comes

  • and you get the chance to save a damsel in distress

  • falling from a helicopter.

  • So, you hold out your arms,

  • hoping to catch her.

  • Seconds later, you will find yourself

  • holding her lifeless body.

  • What happened?

  • Well, pressure is force divided by area.

  • The smaller the area,

  • the bigger the pressure.

  • This is why we can lift heavy objects

  • without breaking our skin,

  • but a tiny needle can make us bleed

  • with just a little poke.

  • The pressure that will be exerted on her body

  • can be calculated by force

  • divided by the area on the top of your arms

  • that comes in contact with her.

  • It doesn't matter if your arms are strong enough

  • to catch her body without breaking your bones.

  • Her spine is not strong enough

  • to be caught by you without being damaged.

  • Even if you rip off the nearest door

  • to provide a bigger area to catch her with,

  • you still wouldn't be able to save her anyway.

  • Remember, it's not the fall that kills her,

  • but the sudden stop at the bottom.

  • Let's say she's falling from a 32 story building,

  • about 300 feet,

  • and you are 6 feet tall,

  • maybe 10 feet on your tippy-toes,

  • with your arms above your head

  • holding a door,

  • in hopes of distributing the pressure

  • across a larger surface area,

  • but all you're doing is essentially moving

  • the ground up by 10 feet.

  • So, she's now falling from 290 feet,

  • instead of 300 feet,

  • reaching the speed of 173 feet per second

  • just before impact,

  • not counting air resistance.

  • It's the equivalent of crashing at 94 miles per hour

  • into a wall with a door in front of it.

  • The only thing that could save her is flying.

  • But that power comes with its own host of scientific issues.

  • If you could fly,

  • what you must do is fly up to her,

  • start flying down at the speed she is falling,

  • hold on to her,

  • then gradually slow down

  • until you come to a complete stop.

  • This process requires a lot of cushion space

  • between the point she starts falling and the ground.

  • Every second you waste

  • on changing into your superhero costume

  • and flying up to her height,

  • her head is getting that much closer to the pavement!

  • If she's falling from a high place,

  • and you can't get to her

  • until she's only a few feet above the ground,

  • there's really nothing you can do

  • other than magically turn the pavement

  • into marshmellow

  • to allow her enough time to slowly come to a stop.

  • Then, break out the chocolate and graham crackers

  • and you've got s'mores.

  • Mmmm, delicious!

  • Now, which superpower physics lesson

  • will you explore next?

  • Shifting body size and content,

  • super speed,

  • flight,

  • super strength,

  • immortality,

  • and

  • invisibility.

If you wake up one morning

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【TED-Ed】If superpowers were real: Super strength - Joy Lin

  • 1917 34
    姚易辰   に公開 2013 年 08 月 28 日
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