Final answer:
The flutist needs to extend the 'tuning joint' of her flute by 464 mm to be in tune with the tuning fork.
Step-by-step explanation:
To calculate how far the flutist needs to extend the 'tuning joint' of her flute to be in tune with the tuning fork, we need to use the equation v = f * λ, where v is the speed of sound, f is the frequency, and λ is the wavelength. First, we need to find the wavelength of the note A played by the tuning fork. Given that the speed of sound is 346 m/s and the frequency is 440 Hz, we can rearrange the equation to solve for λ: λ = v / f = 346 m/s / 440 Hz = 0.786 m. Since we know that the flute produces a musical sound with a speed of 320 m/s and a frequency of 256 Hz, we can rearrange the equation again to solve for the wavelength: λ = v / f = 320 m/s / 256 Hz = 1.25 m. Now, to find the extension needed, we can subtract the original wavelength from the desired wavelength: 0.786 m - 1.25 m = -0.464 m. Since we're looking for a positive distance, we take the absolute value: |-0.464 m| = 0.464 m. Finally, to convert the distance to millimeters, we multiply by 1000: 0.464 m * 1000 = 464 mm. Therefore, the flutist needs to extend the 'tuning joint' of her flute by 464 mm to be in tune with the tuning fork.