It is thought that the range of audible frequencies
decreases with age. Describe an investigation you
could carry out to test this hypothesis
Make sure you include details of the variables you
need to control
1. Connect the signal generator to a speaker
2. Examine the hearing of samples of people: Separate the samples to
be tested by age groups, Make sure that the number of people per
age group is the same. (e.g. 5 10 year olds, 5 30 year olds, 5 60 year
olds, 50 80 year olds) (age is the dependent variable)
3. Examine the hearing of each group at set frequencies, starting from
20 Htz, then 1000 Htz, then 5000, then 10000, then 150000 then
200000, and examine the hearing of each age group. Record your
results in a table (Frequency is the independent variable)
4. Make sure that, during the experiment, the subjects are tested
within the same distance from the sound source, and that they do
not have hearing problems (e.g. due to work in loud areas).
(distance from sound source is a control variable)
5. Make sure that you use the same loudness and amplitude for all
subjects on each frequency (loudness is a control variable)