Respuesta :
Answer:
a) 20 nodes   b) zero nodes
Explanation:
When we have standing waves in a bend we have nodes at the ends and the equation describes the number of possible waves in the string is
     L = n λ/2
Where λ is the wavelength, L is the length of the string, in our case it would be D and n is an entered. We can strip the wavelength of this expression
   Â
    λ = 2L / n
Let's calculate what value of n we have for a wavelength equal to D/10
    λ = 2D / n
    λ = D / 10
We match and calculate
    2D / n = D / 10
    2 / n = 1/10
    n = 20
Perform them for  λ = D / 20
    λ = 2D / n
    2D / n = D / 20
    n = 2 20 = 40
Since n is an inter there should be a wavelength for each value of n in the bone period there should be 20 different wavelengths
B) for La = 10D
    2D / n = 10D
    1 / n = 5
    n = 1/5 = 0.2
Â
La = 20D
    2D / n = 20D
    1 / n = 10
   n = 1/10 = 0.1
These numbers are not entered so there can be no wave in this period
