The period is 4 [insert units here]. To get to this answer you use the equation v= λ*ƒ which basically means velocity is equal to lambda (wavelength) times frequency. Next you insert the speed where velocity is then you insert the wavelength and try to find the frequency. Once you get the frequency which should be 1/4 Hz then you use the proportion: period ~ 1/frequency and then you know that the period is 4.
Frequency = (speed)/(wavelength) = 20/2 = 10 Hz
speed = distance over time = wavelength times frequency = 2 m times 10 hz = 20 m hz = 20 meters per second.
Period = reciprocal of frequency ( 1 / frequency ) = 1/50 = 0.02 second = 20 milliseconds
20/5 = 4 seconds
need to know the speed of the wave at the speed of light 300,000,000 m/s 300,000,000 / 20 = 15,000,000 metres at the speed of sound 333 m/s 333 / 20 = 16.67 metres
40 Hz
.05 seconds
Frequency = (speed)/(wavelength) = 20/2 = 10 Hz
speed = distance over time = wavelength times frequency = 2 m times 10 hz = 20 m hz = 20 meters per second.
Frequency = (speed)/(wavelength) = 10/20 = 1/2
340 m/s
Period = reciprocal of frequency ( 1 / frequency ) = 1/50 = 0.02 second = 20 milliseconds
20/5 = 4 seconds
Wave speed = (frequency) x (wavelength) = (50) x (20) = 1,000 meters.
If a wave is traveling at 5 meters per second (assuming that is what the question meant) and its wavelength is 20 meters, consider standing beside the wave and watching it pass. As the wave is 20 meters long and it is moving at 5 meters per second, it will take 4 seconds for the full cycle of the wave to pass an observer. That means its frequency is one cycle per 4 seconds. And - surprise! - that's the period of the wave. The period of the wave is 4 seconds.
20 miles per hour
The speed of a wave is equal to the product of wavelength x frequency. Just convert everything to standard units (wavelength to meters, frequency to hertz), multiply both, and you'll get the result, also in standard units (meters / second).