On the other hand do you know how to domesticate a horse? I don't, and thats true with a large portion of our skills and technology. As a society we may have high technology and skills but individual knowledge of how to implement it?
A lot would depend on the timeframe you would be dropped to...
If you were shipped back to medieval times do you think you could replicate a toaster/firearm/ICE/etc? Throw on top of that the fact that most people don't know basic survival skills then a lot of that vaunted education and knowledge becomes rather small consolation.
Medieval times? Not too bad. There would be steel available for building stuff from, you would just need the help of a blacksmith to either teach you to do it yourself or do the work for you. Building a steam turbine would not be too difficult; the biggest problem I can foresee is making accurate axles and bearings and keeping the parts in balance to reduce vibrations, and that wouldn't be insurmountably difficult; a metalworking lathe would be required to construct axles and bearing cylinders, but it could be done.
Copper wire could be coated in wax of some kind, barring better alternatives. How to actually make copper wire, you could make a wire pulling device, it's not that complex.
Strong magnets for the generator might actually be the hardest to come by. However, any ferromagnetic material - iron comes to mind first and foremost - would do, as long as you would have a method of magnetizing it. Magnetizing could be done by a direct current electromagnet, and before you say that you wouldn't have current without a generator, I remind you that you can make pretty strong batteries out of something like copper and lead, which were both available in medieval times. Zinc would be better (and less poisonous) than lead, but I dunno how I would come by that in medieval times... Just get enough of copper wire, copper and lead plates, water and something to ionize the water (salt would do) and you get an electric pair that produces direct current. Put a bunch of these in parallel and you can produce pretty high currents, and if you put them in series you can pump the voltages quite high too. You could use that to make strong permanent magnets for the generator.
Gunpowder would not be too hard to make either. Although I would probably want to skip the black gunpowder altogether and go directly to cordite (nitrocellulose and nitroglycerine wouldn't be that much more difficult to manufacture than black gunpowder) and rounds that consist of a shell, round and detonator... none of that muzzle loading garbage.
Again, in medieval times this would not be too hard to do if you could get some connections to aquire the raw materials - in this case, an alchemist and the ever helpful blacksmith.
But yes, I would require assistance from locals to achieve this; however I would know roughly how to do it.
...as a terrifying afterthought, the AK-47 machinery isn't that complicated. Requires a bit of precision tools, yeah. But it could be done. Not immediately of course, it would take years to develope the machinery and equipment to work metals and produce alloys and such, but it could be done. Within, say, 10-15 years of co-operation with an experienced blacksmith we could improve metallurgy to the level where production of Kalashnikov assault rifles would be possible.
Even on bronze age, some of this stuff would be possible. Steam turbine would be less durable and would thus produce less power due to lower rpm's, and bronze in general isn't as good material for stuff like this as steel is, but it would still be doable. Hell, ancient Greeks built a primitive steam turbine, they just didn't think of attaching an axle to it to generate power, and considered it more of a toy despite the fact that it demonstrated the principles of thermodynamics as well as reaction principle.
However, dropped back 20000 years ago and things become significantly harder. You could use some basic mechanical knowledge to build simple machines such as pulleys - a compound bow would be possible to make, but you would again need help from a person experienced in making bows as well as someone experienced with carving wood or bone.
It's a nice thing to ponder though; would you be able to start an industrial revolution at year X?
Moreover,
should you?
