all hardware stores sell adaptors to change from copper to plastic. You solder the adaptor to the copper pipe and attach the plastic pipe to this adaptor using screw clamps to tighten the plastic pipe on the adaptor. To be honest. This answer seems like a bush plumbers answer. To be technically correct. In order for you to connect plastic piping to copper piping one fitting is used and it is called a conex fitting, otherwise called cxc fitting. It has a nut and ring on either side of the joint and this type of fitting can be used on either copper or plastic making it ideal. As you tighten the nut the ring inside tightens onto either the plastic or copper making a water tight connection. It is said above that soldering a copper joint and then attaching it to the plastic pipe is the way but in my experience if you try do that, the heat from the soldering will melt the plastic pipe. Take the safer route and more professional route and use conex fittings.
Use an adapter that glues to the plastic and is threaded to accept a threaded coupling on the copper.
You would have to get the larger sizes cuppler with a reducer to the smaller size and then join it together
If it is a pressure pipe, you would reduce the plastic down to the copper pipes size with reducer fittings and then use one to go to copper. If a waste line and the difference is not too great, you can use a rubber coupling that is the right size on each end and held on with hose clamps.
Nuclear fusion
Tributaries are the smaller rivers and where they join is called a confluence
melt the plastic to the metal
With a plastic joiner
Atomic bonding is the process by which atoms join to form larger substances.
Yes, quite easily
soilder
A threaded copper fitting on the copper side, male or female, and the galvanized is screwed into it.
you can melt them together
No, they are speherical. As they fall faster the air forces them into a pancake shape, which then breaks up into smaller spheres. the smaller spheres may then join with others to make larger spheres and the process may begin again.