Middle School

Forces and Motion

Newton's laws, force diagrams, gravitational, electric, and magnetic interactions.

MS-PS2-1, MS-PS2-2, MS-PS2-3, MS-PS2-4, MS-PS2-5 2 lessons 4 quiz questions

Lesson 1: Forces and Motion

Explain changes in motion using net force and mass.

Learning goals

  • Identify forces acting on objects.
  • Explain net force.
  • Use Newton's laws to predict motion.

Net force

Forces are pushes or pulls. When forces combine, the overall force is the net force. Unbalanced net forces cause changes in motion.

Mass and acceleration

For the same force, an object with less mass accelerates more than an object with greater mass. Motion changes depend on both force and mass.

Lesson 2: Fields and Noncontact Forces

Model gravitational, electric, and magnetic interactions.

Learning goals

  • Describe forces that act at a distance.
  • Compare gravity, electric force, and magnetic force.
  • Use field models.

Forces at a distance

Gravity, electric forces, and magnetic forces can act even when objects do not touch. Their strength depends on properties of the objects and distance.

Fields

A field model represents how an object can exert a force on another object at a distance. Magnetic field lines can show direction and relative strength.