Mythbusters: "Myths Evolution 2"

[Christopher]

Doesn't matter, they used a smashing hammer thing for the frozen head, they should have for the pad lock, in movies they never use a crowbar and hammer, they just smash the thing and it breaks into pieces, this is what needed to be shown.

Were we talking about movies? They never specified that. They were testing whether liquid nitrogen made it easier to break a lock. And it does, and Kari explained the physical, thermodynamic reasons why it does. Extreme cold makes the metal more brittle, period. So a lock frozen by LN would break more easily under a given tool than a room-temperature lock attacked by the same tool. It doesn't matter which tool. As long as they used the same tool for the frozen lock that they did for the unfrozen lock, they've proven the principle, because the temperature of the lock is the only variable that's changed.

 

[Brent]

Doesn't matter, they used a smashing hammer thing for the frozen head, they should have for the pad lock, in movies they never use a crowbar and hammer, they just smash the thing and it breaks into pieces, this is what needed to be shown.

Were we talking about movies? They never specified that. They were testing whether liquid nitrogen made it easier to break a lock. And it does, and Kari explained the physical, thermodynamic reasons why it does. Extreme cold makes the metal more brittle, period. So a lock frozen by LN would break more easily under a given tool than a room-temperature lock attacked by the same tool. It doesn't matter which tool. As long as they used the same tool for the frozen lock that they did for the unfrozen lock, they've proven the principle, because the temperature of the lock is the only variable that's changed.

Yes there were talking about movies, they made it quite clear the idea of using LN2 on locks came from the movies and TV, they even mentioned a couple of series (MacGyver and Burn Notice).

 

[Trekker4747]

Doesn't matter, they used a smashing hammer thing for the frozen head, they should have for the pad lock, in movies they never use a crowbar and hammer, they just smash the thing and it breaks into pieces, this is what needed to be shown.

Were we talking about movies? They never specified that. They were testing whether liquid nitrogen made it easier to break a lock. And it does, and Kari explained the physical, thermodynamic reasons why it does. Extreme cold makes the metal more brittle, period. So a lock frozen by LN would break more easily under a given tool than a room-temperature lock attacked by the same tool. It doesn't matter which tool. As long as they used the same tool for the frozen lock that they did for the unfrozen lock, they've proven the principle, because the temperature of the lock is the only variable that's changed.

Yes there were talking about movies, they made it quite clear the idea of using LN2 on locks came from the movies and TV, they even mentioned a couple of series (MacGyver and Burn Notice).

And in the "golf ball boat rescue" they mentioned a Donald Duck comic. Should Jamie and Adam have dressed up as ducks?

 

[Christopher]

Yes there were talking about movies, they made it quite clear the idea of using LN2 on locks came from the movies and TV, they even mentioned a couple of series (MacGyver and Burn Notice).

But they never claimed to be replicating the exact scenario portrayed in one of those episodes. They were only testing the general question of whether LN2 made it easier to break a lock. And they proved quite effectively that it does. I don't see what the problem is.

 

[Roger Wilco]

The plow was incredible, it didn't even slow down when it cut through the car.

 

[Christopher]

^Not surprising, given that the last time they used that rocket track, the solid plate that smashed into the car essentially disintegrated it. At the kind of velocities those rockets produce, the kinetic energy of the impact is sufficiently greater than the bonding energy that holds the car's molecules together that the impactor barely even "perceives" the car as a solid object.

 

[Roger Wilco]

Yeah, I understand it intellectually and the result wasn't even that surprising to me, but it was still fascinating to see.

 

[Christopher]

To me, the disintegrating car in the earlier myth (their revisit of "Compact Compact") was far more fascinating. I've never seen anything like that. It was like the car was a sculpture of flour and it just went poof when the plate hit it.

 

[Trekker4747]

To me, the disintegrating car in the earlier myth (their revisit of "Compact Compact") was far more fascinating. I've never seen anything like that. It was like the car was a sculpture of flour and it just went poof when the plate hit it.

That rocket-sled hitting the car was simply awesome. It seemed to be the rocket was too as there was a more dramatic change when the second stage ingited.

I think you were right, Christopher, that it didn't split the car so much as it just disintegrated the middle third of the car and the other to halfs to just fell/flew to the side.

It seemed like "over doing it" as far splitting something goes. I'd liken it to chopping wood. To chop a log you hit it with an axe in such a manner that the wood splits but if you were to hit the wood and extreme-ultra speeds you wouldn't split it you'd splinter it. Sure you might end up with "two pieces" of meaningful size, but the bulk of the portion hit would be splinters.