Oklahoma Science PS.PS4.1

ScienceGrades 9–12Waves and Their Applications in Technologies for Information Transfer

The Standard

Use mathematical representations to explain both qualitative and quantitative relationships among frequency, wavelength, and speed of waves traveling in various media.

Oklahoma Academic Standards for Science (2026)

Teacher's field guide

What This Standard Means

What Students Need to Do: Students use wave speed = frequency × wavelength to find a missing value. They explain why wavelength changes when a wave enters a medium where it travels at a different speed, while frequency stays the same.
What Mastery Looks Like: Given a 4 Hz wave moving at 12 m/s, a student calculates a 3 m wavelength. If the wave enters a medium where it moves at 8 m/s, they keep the frequency at 4 Hz and calculate a 2 m wavelength.
Common Misconceptions: Students may think frequency changes when a wave enters a new medium. They may assume a faster wave always has a higher frequency, or divide frequency by speed to find wavelength.
How to Assess It: Exit ticket: A 5 Hz wave crosses from rope A, where it moves at 10 m/s, into rope B, where it moves at 15 m/s. Find its wavelength in each rope and name what stays constant.

Lesson moves

Ways to Teach It

Stretch a slinky at two different tensions; send one pulse each time, film it, and calculate speed from distance and travel time.
Ask: A 3 Hz wave enters a slower medium. What happens to its wavelength, and why? Use wave speed = frequency × wavelength.
Give students speed, frequency, and wavelength cards; have them match valid sets by multiplying frequency and wavelength, then fix one incorrect set.
Compare a 440 Hz sound in air and water using speeds of 343 m/s and 1,480 m/s; calculate both wavelengths.

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