College Board-Aligned Original Notes

AP Physics 2: Algebra-Based Unit 14 Topic 2: Electromagnetic waves

Electromagnetic waves are oscillating electric and magnetic fields that can travel through vacuum.

Unit 14: Waves, Sound, and Physical Optics. College Board exam weighting listed for this unit: 12%-15% of exam score.

What to Know

Electromagnetic waves do not require a material medium.
In vacuum, all electromagnetic waves travel at the speed of light.
The electromagnetic spectrum is organized by frequency, wavelength, and energy.
Always connect this topic back to the larger unit: Waves, Sound, and Physical Optics.

Detailed Notes

Electromagnetic waves belongs to Unit 14: Waves, Sound, and Physical Optics. Electromagnetic waves are oscillating electric and magnetic fields that can travel through vacuum. Start by identifying the system, the field or interaction involved, and which conservation law or model applies.

Key relationships: Electromagnetic waves do not require a material medium. In vacuum, all electromagnetic waves travel at the speed of light. The electromagnetic spectrum is organized by frequency, wavelength, and energy.

Model to use: Represent electric and magnetic fields oscillating perpendicular to each other and to the direction of travel. A clear AP Physics 2 model should label directions, signs, units, and the physical meaning of each variable.

AP-style move: Connect wave frequency to photon energy when the question shifts from classical waves to modern physics. For free-response work, show the governing principle first, then connect the mathematical result back to the physical situation.

Key Vocabulary

Electromagnetic wave

A wave made of oscillating electric and magnetic fields.

Speed of light

The propagation speed of electromagnetic waves in vacuum.

Electromagnetic spectrum

The full range of electromagnetic radiation by frequency or wavelength.

Transverse wave

A wave whose disturbance is perpendicular to its direction of travel.

Radiation frequency

Oscillation rate of electromagnetic radiation.

Quick Practice

How would you explain Electromagnetic waves in one or two AP-style sentences?

Name the concept, apply it to a specific example or source, and explain the reasoning that connects the evidence to your answer.

Official Alignment

Reference and Attribution

AP Physics 2 concept reference: AP Physics 2: Concise Summary Notes by IITian Academy. EduCompanion used this source as a topic checklist and conceptual reference, then rewrote the study notes in original wording.

AP Physics 2: Concise Summary Notes