Question

A guitar string has a length of 0.90 m. When you pluck it, it plays a “C” that has a frequency of 256 Hz. How fast is the wave moving back and forth along the string?

PLZZZ explain how you got the answer!!!!

Answer 1

`v = f * λ \:`

V = Speed

f = frequency of wave

λ = no of wavelengths

Note that in a string, the number of wavelengths is given by;


`(λ)/(2) = l \\ \\ λ = 2l`

l is the length of the string

Hence, λ = 2 × 0.9 = 1.8

Substitute the value of λ in the first equation ;


`v = f * λ \\ \\ v = 256 * 1.8 = 460.8m {s}^( - 2)`