Strange Electromagnet Observation
Hey everyone. I'm fairly new to the hobby electronics world, and today I decided I'd build an electromagnet. I wound my coil around a steel bolt, and I used 3 Duracell AA (1.5V) batteries for a power supply. When I turned on the switch, I found that my beautifully wound coil took a little bit of prying to get it off of the metal base I was working on. I thought "Let's try 9 volts!" So I grabbed a Rayovac 9V battery that I had around and hooked that up in place of the 4.4V (measured) bank. The Rayovac measured to be ~9V. The electromagnet was noticeably weaker. When I tested my magnet with just one of my 1.5V batteries, it felt like it had similar strength to the 9V battery.
Can anyone explain what might be going on?
Short of that, could someone tell me how to measure the current coming off of each power source?