Answer:
19 ms
Explanation:
We need to find the time it takes for the sound from the 6th row gets to the conductor.
Since there are 6 rows and each row is 3 feet apart, since the orchestra is arranged in a semi-circular manner around the conductor, the distance from the 6 th row to the 1st row is (6 - 1) × 3 = 5 × 3 = 15 feet.
Now, since the conductor is 6 feet from the first row, his distance from the 6th row is 15 feet + 6 feet = 21 feet.
So, time approximate delay between the instant when a play at the 6th row start a note and when the conductor hears the note, t = distance between 6th row and conductor/speed of sound.
Speed of sound = 343 m/s
distance between 6th row and conductor = 21 feet. In meters, it is 21 × 0.3048 m = 6.4008 m
t = 6.4008 m ÷ 343 m/s
= 0.019 s
= 19 ms