PLEASE SHOW YOUR WORK. THANK YOU. a) A person stands between two trombonists in

Question

PLEASE SHOW YOUR WORK. THANK YOU.

a) A person stands between two trombonists in a marching band. Each trombonist, playing a frequency of 355 Hz, marches directly away from the listener, one to the listener's right, and one to her left. Each trombonist marches at the same speed of 2.70 m/sec. What beat frequency does the listener hear?

5.589 Hz

0.559 Hz    

0 Hz

7.100 Hz

11.179 Hz

1.118 Hz

b) A person stands on a line between two trombonists in a marching band, one trombonist a distance to the listener's left, and the other a distance to her right. Each trombonist plays a frequency of 390 Hz. One marches toward the listener; the other marches away from the listener. Each trombonist marches at the same speed of 4.50 m/sec. What beat frequency does the listener hear?

10.235 Hz

2.047 Hz    

20.470 Hz

7.801 Hz

1.023 Hz

Explanation / Answer

Since they are producing same frequency and moving away with the same speed,hence they the listener hears the same apparent frequency .So the beat frquency is Zero

So the answer is 0 Hz

Apparent frequency due to marcher towards listener

f1' = (v*f)/(v-Vs) = 343*390/(343-4.5) = 395.18 Hz

due to marcher moving away from the listener

f2'= (v*f)/(v+vs) = 343*390/(343+4.5) = 384.94 Hz

hence the beat frequency is f1'-f2' = 395.18-384.94 = 10.24

So the correct option is 10.235 Hz

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.