6.1.k - 6.1.m Frequency, wave equation, types of waves, meausuring waves

What is pitch?

Pitch is how high or low sound is.
Eg. tight drumskin is a higher pitch than loose drumskin

What does increasing frequency do to colour?

Increasing frequency of light waves changes the colours.
Low to high

Red, Orange, Green, Yellow, Blue, Indigo, Violet

What is frequency?

Number of waves passing a specific point per second. (Hz)

1 hertz = 1 wave passing a point / second

What are the 3 main hertz conversions

Kilohertz = 10 to the power of 3

Megahertz = 10 to the power of 6

Gigahertz = 10 to the power of 9

What is one wave.

One wave has 1 peak and one trough.

What happens to pitch when frequency is increased?

The higher the frequency, the higher the pitch, however the amplitude remains the same.

What is the period of a wave?

Period of a wave is the time taken for each wave to pass a fixed point .

Period, T = 1 / frequency, f

What are the 2 types of waves?

transvers and longitiudinal.

What are transverse waves?

• Energy transfers against the source

• Oscillations at 90 degrees to the direction of the wave.

• Oscillates back and forth

What are examples of transverse waves?

• Water waves on the surface

• Light waves - electromagnetic weaves - can travel through a vacuum (doesn’t need particles)

• S - waves (EQ)

• Mexican Wave

What are longitudinal waves?

• Oscillations are parralel to the direction of energy transfer.

• Oscillates back and forth

What are examples of longitudinal waves?

• P-waves (EQ)

• Sound waves - need a medium (pass through a liquid)

What are the components of a longitudinal waves?

• Wavelength

• Amplitude

• Compression

• Rarefaction

Wavelength of a longitudinal wave

Between 2 compressions

Compression

Region of a longitudinal wave of high pressure because of waves / particles being closer together

Rarefaction

Region of a longitduinal wave of low pressure because of waves / particles being further away.

How can we measure wave speeds?

We need the distance between 2 points of a wave and the time period of the wave passing a specific point.

Wave speed =

Distance / time