| Date | May 2013 | Marks available | 1 | Reference code | 13M.1.HL.TZ2.15 |
| Level | Higher level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | Question number | 15 | Adapted from | N/A |
Question
A stationary source of sound emits sound of frequency f. A moving observer measures the sound as having the frequency f ′. The observer is moving directly away from the source at a speed that is 30% of the speed of sound in air.
Which of the following gives the correct value for \(\frac{{f'}}{f}\)?
A. \(\frac{7}{{10}}\)
B. \(\frac{10}{{13}}\)
C. \(\frac{13}{{10}}\)
D. \(\frac{10}{{7}}\)
Markscheme
A
Examiners report
[N/A]
