Question

why is sulfuric acid present in the electrolysis solution

Answer 1

Water is very weakely ionised and hence does not conduct electricity very well. Sulphuric acid when added to water increases the conductivity of water and thereby speeds up the process of electrolysis.

The acid is necessary for two reasons. First, the solution needs to be conductive in order for plating to take place, and acids like sulfuric acid exhibit great conductivity because of the hydrogen ions they loose. Second, you cannot deposit metal out of solution unless it is in solution, and you can't keep a simple salt of copper in solution at high pH.