How do we know Earth is spinning, not the Sun?

What is the most useful equation for electric power?

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

Imagine that you have two balloons (or, better yet, actually inflate two balloons, if possible). create static electricity around one of the balloons by rubbing it against your hair or your sweater and then bring that balloon close to the other balloon, which has not been charged. try this with at least one other object—and for variety in the discussion, avoid using an object already described by your classmates. then, for your initial post to the discussion, answer the following questions: what happened with the two balloons?