Hello all, I am a computer science graduate who has gotten involved in robotics a lot lately. I am finding myself getting more and more mechanical/physics related questions in my mind, such as this one. The question is: I know how to create an electromagnet by wrapping a big wire around a metal many times and then letting current flow through. What I do not know is where can I find the equations which determine the strength of the magnetic field and what it depends on? Like ... is it the current, the number of turns the coil has?, the size/type of the metal? All of the above? Another question is: Apart from the occasional internet search and my high school physics knowledge is there any book you could advice which I should read in order to refresh on many physics concepts since they seem to pop up more and more in my every day life? Thanks in advance for any answers.