Read the introduction from a science website. Which focus question is the author trying to answer? How does a nine-volt battery work? Electromagnetic force sounds very complicated, but I wanted to understand how it works. My experiment allowed me to create my own electrical field using a nine-volt battery, an iron nail, and some paperclips. This experience helped me understand electromagnetism and the way it works. How does electromagnetic force work? How much electricity is stored in a battery? O How much iron is contained in paperclips?