Answer:
The frequency of wave is 160Hz.
Explanation:
Given that the formula of speed is V = f×λ where V represents speed, f is frequency and λ is wavelength.
So first thing, you have to make frequency the subject by dividing wavelength on both sides :
[tex]v = f \times λ \: [/tex]
[tex]v \div λ = f \times λ \div λ[/tex]
[tex]f = \frac{v}{λ} [/tex]
Next you have to substitute the value of v and f into the formula :
Let λ = 2.5m,
Let v = 400m/s,
[tex]f = \frac{400}{2.5} [/tex]
[tex]f = 160Hz[/tex]