Lesson Plan: Newton’s Third Law of Motion Physics • First Year of Secondary School
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to define Newton’s third law of motion and to apply Newton’s laws of motion to analyze systems of forces.
Objectives
Students will be able to
- understand that Newton’s third law of motion applies to pairs of objects rather than to individual objects,
- understand that all forces are forces between two interacting objects,
- understand that forces between two interacting objects always occur in pairs,
- recall that pairs of objects exert equal magnitude forces on each other,
- recall that the forces exerted by a pair of objects on each other act in opposite directions,
- recall that a pair of forces consistent with Newton’s third law must be of the same type (such as gravitational or electromagnetic),
- recall that some of the forces that pairs of objects exert on each other act only during contact and some others act without requiring contact,
- recall that the forces that pairs of objects exert on each other can be mutually attracting or mutually repelling; gravitational forces can only attract but electromagnetic forces can either attract or repel.
Prerequisites
Students should already be familiar with
- ,
- .
Exclusions
Students will not cover
- forces other than gravitational, reaction, and tension forces,
- mechanisms of production of forces,
- velocity changes of objects due to forces that they exert on each other.
