Which of these cannot travel through a vacuum?

What do we call the height of a wave?

What do we measure in Hz in sound waves?

What describe the spreading out of a wave after it has passed through a gap?

What size gap causes significant diffraction?

What are the units of frequency?

How do we calculate the frequency of a wave?

What is the period of a wave?

Which of these is not a type of electromagnetic radiation?

What is the wave speed equation?