A wave transfers energy away from its [.........] .
A wave transfers energy away from its SOURCE
What can we also call a moving wave?
A progressive wave
How does a Progressive wave transfer energy?
Carries energy from one place to another without transferring any material
Which direction is the transfer of energy from a wave?
The same direction the wave is travelling
Examples of waves that carry energy.
- Electromagnetic waves cause things to heat up - X Rays and Gamma rays knock electrons out of their orbits, causing ionisation
Diagram of a Wave (Transverse).
What is the Displacement of a wave?
How far a point has moved from its undisturbed position
What is the Amplitude of a wave?
The Maximum magnitude of the displacement
What is the Wavelength of a Wave?
The length of one whoe wave cycle, eg. crest to crest OR trough to trough
What are Wavelength, Amplitude & Displacement measured in?
What is the Period of a Wave?
The time talen for a whole cycle (vibration) to complete
What is the frequency of a wave?
The number of cycles (vibrations) per second passing a given point
What is the a Phase of a Wave?
A measurement of the position of a certain point along the wave cycle
What is the Phase Different of Waves?
The amount one wave lags behind another
What is the units for Frequency?
What is the equation for frequency including Period?
Frequency = 1/Period
What is the Wavespeed equation? (with distance and time)
Wave Speed = Distance / Time
v = d/t
What is the wave speed equation? (including Frequency and wavelength)
Wave Speed = Frequency X wavelength
v = fλ
What does a Cathode Ray Oscilloscope measure?
On a Cathode Ray Oscilloscope what are the splits in the screen called?
On a Cathode Ray Oscilloscope the vertical axis is in [......]
What button controls the volts per division on the vertical axis?
The gain dial
On a Cathode Ray Oscilloscope the horizontal axis is in [....]
On a Cathode Ray Oscilloscope what is the seconds per division controlled by?
The timebase dial
Why do you alter the gain and timebase dial?
To make it easy to read off measurements
A [........] converts sound waves into electrical signals which can be seen on an oscilloscope.
What can an oscillopscope be used for?
Used to find the speed of sound
Diagram of the Apparatus needed to measure the speed of sound.
When measuring the speed of sound what kind of Oscilloscope must be used and why?
A 2-beam oscilloscope so it can display two waves - one for the signal generator generating the sound wave and one for the same sound wave being received by the microphone.
Method of Measuring the Speed of Sound?
1 - Set up apparatus
2 - Twist gain and timebase dials so you can see one complete cycle of each wave
3 - Change the distance between the microphone and loudspeaker sp the the peaks of wave A line up with the troughs of wave B and measure the distance.
4 - Calculate the frequency of the wave by finding the period and using f = 1/T because oscilloscope has a better resolution and gives a smaller uncertainty
5 - Move the microphone so that the wave on the oscilloscope moves one full wavelength along the signal generator, measure the distance
6 - Distance betweem your two measurements is the actual wavelength
7 - Repeat steps 5 -6 and use your results to find a mean
8 - Use equation v = f/λ to find the speed of sound