Draw me a wave!
YouTube - Water bubble in Space (zero gravity)
•Define a wave
•Differentiate between longitudinal and transverse waves (with
•Define amplitude, wavelength, frequency and period of a wave
•Describe the relationship between frequency and period
•Use the wave equation
Waves can transfer energy and
information without a net motion of the
medium through which they travel.
They involve vibrations (oscillations) of
Rays indicates the direction of energy
The oscillations are perpendicular to
the direction of energy transfer.
Direction of energy transfer
Amplitude - A
The maximum height of the wave from
the middle line position.
Frequency - f
The number of complete waves
(oscillations) in one second. Measured in
50 Hz = 50 vibrations/waves/oscillations in one second.
Frequency – The number of
waves per second. If one wave
passes in one second it has a
frequency of one Hertz or Hz. This
is the unit of frequency.
Wavelength - λ
The length of one complete wave.
Wave speed - v
The speed at which the wave fronts
pass a stationary observer.
The Wave Equation
V = speed of wave (m/s)
f = frequency of wave (Hz)
λ = wavelength (m)
v = fλv
1) A water wave has a frequency of 2Hz and a wavelength of
0.3m. How fast is it moving?
2) A water wave travels through a pond with a speed of 1m/s
and a frequency of 5Hz. What is the wavelength of the
3) The speed of sound is 330m/s (in air). When Dave hears
this sound his ear vibrates 660 times a second. What was
the wavelength of the sound?
4) Purple light has a wavelength of around 6x10-7
m and a
frequency of 5x1014
Hz. What is the speed of purple light?
Group wave equation questions