I've been continuing to work my way through Barry Luokkala'a great book, Exploring Science through Science Fiction - and I really liked his take on this scene - in which Bond escapes from a train that is about to explode, by cutting his way through 1 inch steel with the laser that has been helpfully built into his watch.
Luokkala asks, as he does for many scenes in his book, if the scene is plausible. And in Bond, we don't have to stretch credulity quite as far as we do in some science fiction (see here for example): lasers are frequently used to cut through steel and have been used to do so since the 1960s. In fact the issue first arose in a Bond film in 1966 when Goldfinger was well on his way to slicing Sean Connery in half when he was persuaded to switch his laser off. At that point, the laser had only been developed and it was a little futuristic. But by the time Goldeye came out, the idea was old-hat.
Nonetheless, it is still valid to ask if a laser would be sufficiently powerful to cut through the floor of the train within the time available, and if there is any chance that a watch battery could hold sufficient energy to do so.
To get students to work through this, I fed them some information. It's a pity to do that in a way - as half the fun is digging deep into your own assumptions and finding the relevant data online. But I think it's needed to fit this into a reasonable amount of time and come close to matching the sort of problem-solving questions students will ultimately meet in the Leaving Cert.
And our conclusions? Yes, a laser could cut though the steel floor in the time given. But no, it couldn't be powered by a watch battery!
The work involves an overview of both specific heat capacities and latent heats, along with a bit of work on power/energy and on mass/volume/density - which I think justifies the time spent. Its all included in a PowerPoint here.
And it also allowed us to argue the rival merits of the many actors who have now played Bond, which is always fun. (To my mind - though not to any of my student's - Brosnan comes in at number 2. Because he disdained any of that Bond-with-feelings nonsense and stuck to gadgets and gags.)