A stone is thrown into water pond forming 10 waves in 5 seconds. The diameter of the first crest is 13 m and the diameter of the last crest is 4m. Find
a.the periodic time
b.the frequency
c.the wave length
d.the wave velocity
R1 = 13/3 = 4.33 m
R10 = 2 m
T = 5 seconds / 10 waves = .5 s
f = 1/T = 2 Hz
wavelength = (4.33-2)/9 = .259 meter
v = .259/.5 = .518 m/s
To find the periodic time, divide the total time taken by the number of waves.
a. Periodic time:
Periodic time = Total time / Number of waves
Periodic time = 5 seconds / 10 waves
Periodic time = 0.5 seconds
To find the frequency, divide the number of waves by the total time taken.
b. Frequency:
Frequency = Number of waves / Total time
Frequency = 10 waves / 5 seconds
Frequency = 2 waves per second or 2 Hz (Hertz)
To find the wavelength, calculate the difference between the diameters of the first crest and the last crest.
c. Wavelength:
Wavelength = Diameter of the first crest - Diameter of the last crest
Wavelength = 13 m - 4 m
Wavelength = 9 m
To find the wave velocity, multiply the wavelength by the frequency.
d. Wave velocity:
Wave velocity = Wavelength * Frequency
Wave velocity = 9 m * 2 Hz
Wave velocity = 18 m/s
So, the answers are:
a. The periodic time is 0.5 seconds.
b. The frequency is 2 Hz.
c. The wavelength is 9 meters.
d. The wave velocity is 18 m/s.