Lesson 14 (Rotation and Torque) of Dianna's Intro Physics Class on Physics Girl. Never taken physics before? Want to learn the basics of physics? Need an AP Physics 1 review before the exam? This course is for you! Exercises in this video: 1. If you are standing on Earth’s equator (radius about 6380km), how fast are you going? What is your rotational velocity? What is your angular velocity? 2. A tiny cat, mass 0.50kg is clinging to the edge of a record spinning at 45rpm. If the radius of the record is 0.10m, what is the frictional force keeping that cat moving in a circle? 3. If Dianna, mass 60 kg, is standing on a scale on the equator, what does the scale actually read? 4. Dianna and Marie want to balance on a seesaw. But Marie has 3 times Dianna’s mass. How far away from Dianna should they move the fulcrum in order to balance the seesaw? Special thanks to propulsion engineer Diana Alsindy for her awesome shoutout at the end of the video! You can follow her on Twitter @DianaAlsindy Credits: Dianna Cowern - Executive Producer/Host/Writer Jeff Brock - Lead Writer/Course Designer Laura Chernikoff - Producer Rachel Watson - Video Editor Sophia Chen - Researcher/Writer Erika K. Carlson - Researcher/Writer Hope Butner - Production Assistant Levi Butner - Videographer Lauren Ivy - Set Design Vanessa Hill - Consulting Producer Aleeza McCant - Illustrator Rachel Allen - Illustrator Consultant - Kyle Kitzmiller Lucy Brock, Samantha Ward - Curriculum Consultants Cathy Cowern - Transcription