Question

2. A string with a length of 0.9m that is fixed at both ends

a) What is the longest possible wavelength for the travelling waves that can
interfere to form a standing wave on this string?(First harmonic)
b) If waves travel at a speed of 120m/s on this string, what is the frequency
associated with the longest wave (first harmonic)?
3. Suppose that the string in #2 is plucked so that there are two nodes along the
string in addition to those at either end.
a) draw or sketch the wave produced in the situation
b) Calculate the wavelength for this interfering wave.

Answer 1

2a.) Wavelength = 1.8 m

2b.) F = 66.67 Hz

3a.) Find the attached file

3b.) Wavelength = 0.6 m

Step-by-step explanation:

Given that the

Length L = 0.9m

Wavelength (λ) = 2L/n

Where n = number of harmonic

If n = 1, then

Wavelength (λ) = 2L = 2 × 0.9 = 1.8 m

b.)

If waves travel at a speed of 120m/s on this string, what is the frequency

associated with the longest wave (first harmonic)?

Given that V = 120 m/s

V = Fλ

But λ = 2L, therefore,

F = V/2L

F = 120/1.8

F = 66.67 Hz

3. b.) If there are two node, the position will be in 3rd position which is 3rd harmonic

Using the same formula,

Wavelength (λ) = 2L/n

Where n = 3

Wavelength (λ) = 2 × 0.9/3

Wavelength (λ) = 0.6 m