Lesson 5 (Free Body Diagrams) 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:
Problem 1: Draw a free body diagram (FBD) for a bottle of nail polish falling straight down. Draw a FBD for a soccer ball kicked at at an angle, after the kick. What about during the kick?

Problem 2: You are standing on a scale in an elevator that is accelerating upwards at a rate of 2.0 m/s². If your mass is 58kg, what does the scale read in Newtons? What would it read if you were decelerating at 2.0m/s² (accelerating at -2.0 m/s²)
Problem 3: We built a human-sized Atwood machine using two masses: 65kg and 79kg. The masses fell 2.0 meters from rest and it took 2.2 seconds. What do we get for “g”? What are some possible sources of error?
Problem 4: You build an Atwood Machine where the masses have a ration of 4:5. What will the acceleration of the masses be?
Special thank you to the amazing Bill Nye for his shoutout at the end of the video!
Credits
Dianna Cowern - Executive Producer/Host/Writer
Jeff Brock - Lead Writer/Course Designer
Laura Chernikoff - Producer
Spenser Reich - Video Editor
Sophia Chen - Researcher/Writer
Erika K. Carlson - Researcher/Writer
Hope Butner - Production Assistant
Levi Butner - Videographer
Kyle Kitzmiller - Consultant
Andy Brown - Curriculum Consultant
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