A string 1.30 meters in length is oscillating in its first harmonic. The frequency of oscillation is 7.80 Hz. What is the wavelength of the first harmonic?

2.6m

Explanation:

The formula for calculating the wavelength is expressed as;

λ = v/f

v is the velocity

f is the frequency of vibration

Given

f = 7.80Hz

We need to get the velocity

For string;

f = V/2L

7.80 = V/2(1.3)

7.80 = V/2.6

V = 2.6 * 7.8

V = 20.28m/s

Get the required wavelength

λ = v/f

λ = 20.28/7.80

λ = 2.6m

Hence  the wavelength of the first harmonic is 2.6m

terd muffin is the correct answer