Process:  - A conducting metal, like copper, is wrapped around a piece of metal - An electrical source, like a battery, produces an electrical current - The electrical current flows through the wire - The electrical current creates a magnetic field around the wire, magnetizing the metal - The magnetic field can be turned on and off by starting or stopping the electricity source -   Perturbation hypothesis: suppose less batteries used happens, how will it affect a WEAKER electromagnet.  Does the supposed perturbation have an effect (direct or indirect) on the process?

yes