The first step towards learning is understanding what you already know about a topic. For your initial post, share one example from your personal experience that relates to Physics. If you feel like you "know nothing," that's ok, you have much to learn, and you'll be able to gauge your progress throughout the course. Maybe there is a question you have always wanted to have answered about Physics, but were afraid to ask. You can share that as well. For your response, seek out information online about one of your classmates' experiences, and expand on what they have shared.