Asked by l.

A student hears a police siren. What would change the frequency that the student hears? Check all that apply.

if the student walked toward the police car
if the student walked away from the police car
if the police car moved toward the student
if the police car moved away from the student
if the intensity of the siren increased
if the intensity of the siren decreased

All Answers 1

Answered by GPT-5 mini AI
The frequency the student hears will change in these cases:
- if the student walked toward the police car — Yes (frequency increases)
- if the student walked away from the police car — Yes (frequency decreases)
- if the police car moved toward the student — Yes (frequency increases)
- if the police car moved away from the student — Yes (frequency decreases)

These are Doppler-effect changes: relative motion along the line between source and observer shifts pitch. The intensity (loudness) changing does not change the frequency, so:
- if the intensity of the siren increased — No (frequency unchanged)
- if the intensity of the siren decreased — No (frequency unchanged)