Core Practicals Paper 1

Question 1

Speed of sound measure

Answer 1

Connect signal generator at set frequency to oscilloscope with 2 microphones.
Set them up so that the wave lengths are SEPARATE waves.
Start with both microphones next to speaker and slowly move one microphone away until 2 waves are aligned but have moved one wavelength apart.
Distance between microphones = 1 wavelength
Use v = frequency * wavelength

Question 2

Measure the speed of water ripples

Answer 2

Attach dipper to signal generator at set frequency in dark room with UV lights and change the frequency of the UV lamp until the waves don’t appear to move. Frequency of UV lamp= frequency of water waves.
Measure 10 wavelengths apart and find average wavelength.
The distance between each line= one wavelength

Question 3

Speed of waves in solid

Answer 3

Attach metal rod to elastic band (at center) and measure length.
Attach microphone to computer and measure peak frequency of the wave when an object is hit against it. One wavelength = 2 * the length of the rod.
Repeat three times to get average peak frequency.