Tutorial details

Section I: Applying Newton’s laws at constant speed

Students consider three bricks pushed across a table at constant speed. The bricks are split into two systems: one consisting of a single brick and the other consisting of two. After comparing the net force on each system and constructing free-body diagrams, students apply Newton’s second and third laws to rank the magnitudes of all the forces.

Section II: Applying Newton’s laws at varying speed

Students consider a similar scenario, but with non-zero acceleration. They again determine the forces on each system, construct free-body diagrams, and apply Newton’s laws to rank the magnitudes of the forces. In Questions H-J, students construct a free-body diagram and identify internal & external forces for the system of all 3 blocks.

Section III: Interpreting free-body diagrams

Students interpret the free-body diagram for a cart and create a sketch of the physical situation. They then use the forces on the diagram to reason about the possible motions of the cart.

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This tutorial works best if students have previously been introduced to Newton’s second and third laws in lecture. They should also be familiar with normal, frictional, and gravitational forces.

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