Frequency is the Number of Waves passing through a Point in One Second
Given : The Frequency of the Wave is : 700 Hz
Given : The Wavelength of the Wave is : 6 meter
⇒ In One second 700 waves of Wavelength 6 meter cross the point
⇒ In One second the First wave travels : 700 × 6 meters
⇒ In One second the First wave travels : 4200 meter
⇒ The Speed of the wave is : 4200 m/sec