Physics: Why Doubling Turns Doubles the Magnetic Pull

Electromagnetism is the study of how electric current generates magnetic fields, and nowhere is this relationship more tangible than in a simple electromagnet: a coil of insulated wire wrapped around an iron core. Increasing the number of turns strengthens the field, and this strength can be measured by how many paper clips the magnet lifts. The key idea is direct proportionality: paper clips lifted = number of turns ÷ 5, so the ratio of turns to clips stays constant. Doubling the turns doubles the clips lifted, because each additional loop contributes equally to the magnetic effect. This linear relationship lets you predict magnetic strength from coil design, or work backwards to find the turns needed to match a permanent bar magnet's lifting power. Understanding it connects coil geometry to field strength, forming the foundation for motors, relays, and loudspeakers.