Why do transformers need lots of turns or winds on the primary?

Why not fewer winds with thicker wire to get stepup or stepdown.



Instead of 200 winds on the primary ,how about 20?



It would be same ratio?Why do transformers need lots of turns or winds on the primary?if you had only 20 windings instead of 200 then the conductor would be much shorter and have less resistance meaning more current would flow generating more heat, so you would have to have a larger cross sectional area on the conductor to compensate, witch means less resistance again resulting in greater current flow generating even more heat. so your transformer would be bigger, heavier, running very hot and more expensive than it needs to be.

so by increasing the number of windings your increasing the length of the conductor and so increasing the resistance, decreasing the current and heat enabling you to use a smaller cross sectional area making the transformer smaller and most importantly,,, cheaperWhy do transformers need lots of turns or winds on the primary?A bigger wire would have more free electrons and more surface area so it would be less reactive meaning it has more resistance.



I am sure that some how beyond my knowledge this would throw the entire system out of whack.



Maybe if you had a wire that was made of something different so that you can get the same conducting capability as the smaller wire on the secondary coil?



I am pretty sure that the change in wire size would also change the magnetic field though just to mess something else up.