**Standing Waves in Strings – Practice**

**Questions:**

1) A string is 65cm long and fixed at both ends?

a) What is the wavelength of the first harmonic:

b) If the frequency of the first harmonic is 350Hz, what is the frequency of the third harmonic?

2) The first harmonic of a 0.60m guitar string is 800Hz.

a) What are the frequencies of the second, third and fifth harmonic?

b) What is the speed of the waves in the string?

c) What is the wavelength of the first harmonic?

d) Is it possible to have a frequency of 1200Hz?

3) A cable used in a sound experiment is 35cm long and has a mass of 5gms. The tension in the string is 50N.

a) What is the velocity of the wave in this string?

b) What is the fundamental frequency of this string?

4) The second harmonic of a 1.2m length of string has a frequency of 360Hz. How fast is the wave travelling through this string?

**Quick**** Answers:**

1a) 1.3m

1b) 1050 Hz

2a) f_{2} = 1600 Hz, f_{3} = 2400 Hz, f_{5} = 4000Hz

2b) 960 m/s

2c) 1.2 m

2d) No.

3a) 59.16 m/s

3a) 84.5 Hz

4) 432 m/s

**Worked Answers:**