Question

What is the number of phons for a 1000 Hz pure tone at 40 dB?

a) 40
b) 30
c) 20
d) 10

Answer 1

c) 20. The loudness of a 1000 Hz pure tone at 40 dB is approximately 20 phons.

Step-by-step explanation:

The loudness of a sound is measured in phons and is based on the sound's frequency and intensity level. To determine the number of phons for a 1000 Hz pure tone at 40 dB, we can refer to the graph in Figure 17.34. If we locate the point on the graph where the frequency is 1000 Hz and the intensity level is 40 dB, we can interpolate between the loudness curves to find the loudness in phons.

Based on the graph, we can estimate that the loudness of a 1000 Hz pure tone at 40 dB is approximately 20 phons.

Therefore, the answer is c) 20.