Mitch: Hello, and welcome to The Lab, where we take your questions and turn them into experiments

My name is Mitch,

Greg: And I'm Greg,

and today, we're gonna be conquering one of our greatest fears, which is the fear of height.

Mitch: Specifically, we're gonna be climbing one of the tallest free-standing structures in the western hemisphere

and finding out what would happen if we fall off.

Greg: The fear of height is also known as acrophobia,

and the symptoms include dizziness, nausea, shaking...

So we're gonna test these things on ourselves by going up to CN Tower,

going outside of it, and walking around the edge.

Mitch: The CN Tower is an iconic part of the Toronto skyline and stands 553 metres high.

Greg: It's also Drake's favourite chair.

The long, pointy antenna portion was actually made up of 26 pieces, each which were brought up by a helicopter.

Mitch: But where we'll be completing our edge walk is on the top of the main pod,

which is 356 metres above the ground and is the highest external walk of a building in the world.

Greg: For reference, it would be like stacking the White House on top of itelf approximately 17 times,

and then walking around on top.

[music]

Greg: How you feeling, Mitch?

Mitch: I'm nervous. That's what we're going on right in a couple of seconds, and I realise I have a fear of heights all of a sudden.

Greg: I'm not nervous but seeing it when I got here, I'm scared. But I'm not scared at all.

Mitch: Yeah, you're scared. I know you are. You're just kinda being a [talking too fast to be understood]

Our brains are basically anticipation machines and we use information from our past, and our current state, and our environment to help predict the future,

which, ultimately, helps us stay alive.

Greg: Mitch is signing away his life.

Hopefully you don't fall off!

Mitch: But, when you don't have any experience with the thing that you're anticipating,

like, I've never been hundreds of metres in the air walking on an edge that I can DIE off of,

then your fear goes up and so does your fight-or-flight behaviour.

I thought you weren't nervous?

Greg: I'm not.

Mitch: So I have to pee, because, obviously, I'm getting nervous and

I'm freaking out. My bladder is like, "Let loose!".

Lady: You guys look good! You look like... you looking beautiful!

Greg: A lot of our fears stem out of learned experiences or traumatic events that have happened to us

but the fear of heights is said to be much more common in people and it's actually something that we're born with.

Mitch: When we go up the elevators, I go freak out.

Greg: I don't feel anything. I actually don't because it just feels like I'm just wearing a cool suit.

Scientists have actually used studies and experiments with visual cliffs,

and they study domestic animals and toddlers and found that at a very young age,

they're very cautious around these cliffs, showing that the fear of heights is something that we're born with.

I've got adrenaline; this is good.

I'm also, like, "Where's my helmet?"

I mean, it makes sense that the fear of heights is natural and something that we're born with,

because it protects ourselves and makes us live longer so that we don't walk off cliffs or walk off the CN Tower.

Guide: Hey, Greg, come check it out!

Greg: [screaming]

I'm shaking now and I'm feeling kind of sick - that is crazy!

Mitch: Woah!

Greg: But, this can hold 15 and a half thousand pounds so we're hoping that we're fine.

Greg: How's it going?

Mitch: Ugh... (anxious)

Guide: The third, yep, right there. Push your rope all the way all the way out in front of you

and then lean forward in that room.

Mitch: Ahhhh...

Guide: Keep going, all the way forward.

Excellent, and then you can let go!

Awesome job, Mitch!

Alright! Yeah! Go up on your toes.

Mitch: Ahhhhhhhhhhh!!!!!!

Guide: Excellent!

[Music]

Greg: Okay, so this is amazing, horrifying, and I'm freaking out but imagine if you fell - what would happen?

Mitch: Well, a 77 kilogram person falling from 356 metres would reach speeds of up to 300 kilometres an hour

and reach the bottom in under 9 seconds.

That is, without any drag or force acting opposite to the relative motion of a moving object.

Top terminal velocities for human skydivers are lower because of air resistence,

around 195 kilometres an hour when facing stomach to earth,

and they don't reach this speed until around 12 seconds or after travelling 450 metres.

Either way, it wouldn't take long to hit the bottom.

Greg: It's no surprise that you likely wouldn't survive this fall, although some humans have lived to tell the tale

after falling from very high heights.

In fact, there's actually been reports of people falling from over 5,000 metres,

mostly during the war, so out of burning airplanes, but they landed on pine trees, or soft snow or glass roofs

and they also had a lot of injuries.

Mitch: It ultimately depends on if the surface you land on has high deformity, like snow, then your chances for survival increase.

Mitch and Greg: Okayyyyy.

Greg: I feel less dizzy and scared now.

Mitch: I feel more confident now that we've had some time

to spend staring; it kind of becomes normal after a while.

Greg: Yeah, and now, I'm like, "What's that? What's that?"

Mitch: But, everytime I have to go on the edge I'm still in genuine fear.

Greg: And it's the toes over the edge that makes me want to throw up.

Mitch: It was a crazy experience but super cool, we're so glad we did it. Conquered a fear!

Guide: Awesome job, Greg! Well done, Mitch!

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