A train moving with constant speed towards an observer on a nearby bridge sounds its horn
PHYSICS · Single correct · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics
Problem
A train moving with constant speed towards an observer on a nearby bridge sounds its horn, which emits a sound of frequency f.
As the train approaches the observer, which of the following statements is correct?
(1) The observer hears a sound of frequency smaller than f and with a constant intensity.
(2) The observer hears a sound of frequency smaller than f and with an increasing intensity.
(3) The observer hears a sound of frequency larger than f and with a constant intensity.
(4) The observer hears a sound of frequency larger than f and with an increasing intensity.