A Tucson teacher is under investigation after sending sixth-grade students home with an assignment that included lyrics from a rap song depicting drugs, sex, gambling and violence. The Tucson Unified ...

Here's how to tell the old and new AirTags apart, and how the second generation improves on the original. Jeff Carlson writes about mobile technology for CNET. He is also the author of dozens of ...

Note that all forces on the system act at the fixed point O. What does this say about the angular momentum of the system about point O? Also, consider the work/energy equation for the system.