Question 22M.2.HL.TZ1.d
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.HL.TZ1.d |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Determine | Question number | d | Adapted from | N/A |
Two loudspeakers A and B are initially equidistant from a microphone M. The frequency and intensity emitted by A and B are the same. A and B emit sound in phase. A is fixed in position.
B is moved slowly away from M along the line MP. The graph shows the variation with distance travelled by B of the received intensity at M.
Loudspeaker A is switched off. Loudspeaker B moves away from M at a speed of 1.5 m s−1 while emitting a frequency of 3.0 kHz.
Determine the difference between the frequency detected at M and that emitted by B.
[2]
ALTERNATIVE 1
use of (+ sign must be seen) OR = 2987 «Hz» ✓
« » = 13 «Hz» ✓
ALTERNATIVE 2
Attempted use of ≈
« Δf » = 13 «Hz» ✓
Many candidates were successful in setting up a Doppler calculation and determining the new frequency, although some missed the second step of finding the difference in frequencies.
