To determine which wave has the lowest frequency, we can use the wave equation:
\[ f = \frac{v}{\lambda} \]
where:
- \( f \) is the frequency,
- \( v \) is the wave speed,
- \( \lambda \) is the wavelength.
Given that all waves have the same speed of \( 600 , m/s \), we can calculate the frequency for each wave using their respective wavelengths:
-
Wave L:
\[ f_L = \frac{600 , m/s}{120 , m} = 5 , Hz \] -
Wave M:
\[ f_M = \frac{600 , m/s}{150 , m} = 4 , Hz \] -
Wave N:
\[ f_N = \frac{600 , m/s}{100 , m} = 6 , Hz \] -
Wave O:
\[ f_O = \frac{600 , m/s}{50 , m} = 12 , Hz \]
Now comparing the frequencies:
- Wave L: 5 Hz
- Wave M: 4 Hz
- Wave N: 6 Hz
- Wave O: 12 Hz
The lowest frequency is from wave M with a frequency of 4 Hz.
So, the answer is wave M.