CurriculumGrade 8Science

Amplitude, Wavelength & Wave Energy

Aligned to MS-PS4-1 — Next Generation Science Standards.

What this lesson teaches

A wave can be described by its amplitude (its height) and its wavelength (the distance between crests). A larger amplitude carries more energy, while wavelength sets how the wave is spaced.

Worked example

A gently plucked guitar string makes a quiet sound with a small amplitude, but plucking it harder raises the amplitude and the sound gets louder, because the wave now carries more energy.

Practice questions

  1. Measure the amplitude and the wavelength on a diagram of a transverse wave.
  2. Compare two waves and use their amplitudes to predict which one carries more energy.
  3. Explain how the wave model represents a louder sound versus a softer one.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

Amplitud, Longitud de Onda y Energía

Una onda se puede describir por su amplitud (su altura) y su longitud de onda (la distancia entre crestas). Una amplitud mayor lleva más energía, mientras que la longitud de onda determina cómo está espaciada la onda.

Ejemplo: Una cuerda de guitarra pulsada suavemente hace un sonido bajo con poca amplitud, pero pulsarla con más fuerza aumenta la amplitud y el sonido se vuelve más fuerte, porque la onda ahora lleva más energía.

More Waves & Their Applications lessons

Reflection, Absorption & TransmissionMS-PS4-2

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