Question

TULA. Each multiple-choice question is worth 4 points - you must circle the most correct answer (2 points) and justify your answer (2 points). 1. A fire truck approaches you with its siren on. Which of the following statements is false about the signal you receive from the fire truck? a. The siren sounds louder to you. b. The frequency of the sound increases. C. The wavelength of the sound decreases. d. The speed of the sound increases. Explain your reasoning. 2. Which color of light has the greatest speed? a. Red b. Green c. Violet d. All colors have the same speed.n et Explain your reasoning. e Vound of SWE vent or the shit of the average mais Svewoensmotto blens lon si powolololo

Answer 1

Answers:

Question (1) Answer : (d) the speed of the sound increase is a false statement.

Since, Speed of sound does not depend on the motion of the source.

According to Doppler effect which says that there will be a change in frequency of a wave for an observer moving relative to its source. The observer observes an upward shift in frequency when the wave source is approaching, and a downward shift in frequency when the wave source is retreating. Since, the truck is approaching - So, its frequency will be increased.

Question (2) Answer : (d) All the colors have the same speed.

Because, All the colors travels in the form of electromagnetic radiation, and speed of electromagnetic radiation remains same in the same medium.