Half Atwood Machines

Overview

Link to Experience: https://play.phenomena.app/player/PopvK2P4mIvtJL4VWC7u

Topics: physics, force, Atwood machines, net force, tension, kinematics, mass, acceleration, Newton’s second law

Grades: 11-12

Standards: NGSS HS-PS2-1

Duration to complete: 10-15 minutes

Learning outcome: Students will be able to read the free-body diagrams that can be drawn on a half Atwood machine, will gain a deeper understanding of Newton’s Second Law, and will be able to calculate net force and tension.

In the Classroom

Pre-Experience (Things to Look Out For):

• Review: What is Newton’s Second Law?

• Have you ever used an Atwood machine before? What do you think they do?

• What forces are involved in an Atwood machine?

Post-Experience (Things to Think About):

• What is the net force acting on the mass moving horizontally?

• What is the net force acting on the mass moving vertically?

• How do you think introducing friction would affect the Half-Atwood Machine?

• How can you increase the acceleration of a Half-Atwood Machine?

• Does tension differ on both sides of the rope? Why do you think that is?