CurriculumGrade 4Science

Waves: Amplitude & Wavelength

Aligned to 4-PS4 — Next Generation Science Standards.

What this lesson teaches

Waves carry energy. A wave's amplitude is its height (bigger amplitude = more energy, louder sound), and wavelength is the distance between peaks. Light and sound both travel as waves.

Worked example

Plucking a guitar string harder makes a louder note — same pitch, bigger amplitude. A bigger ocean wave (more amplitude) hits the shore with more force.

Practice questions

  1. What changes about a sound wave when a sound gets louder?
  2. How do waves carry energy without carrying matter across the ocean?
  3. Draw a wave and label amplitude and wavelength.

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

Ondas: Amplitud y longitud de onda

Las ondas transportan energía. La amplitud de una onda es su altura (mayor amplitud = más energía, sonido más fuerte), y la longitud de onda es la distancia entre crestas. La luz y el sonido viajan como ondas.

Ejemplo: Rasgar una cuerda de guitarra con más fuerza produce una nota más fuerte — mismo tono, mayor amplitud. Una ola del océano más grande (mayor amplitud) golpea la orilla con más fuerza.

More Physical Science lessons

Energy and Energy Transfer4-PS3How Energy Travels4-PS3-2When Things Collide4-PS3-3Energy-Changing Machines4-PS3-4How We See Things4-PS4-2Sending Messages with Patterns4-PS4-3

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