Question

The wavelength,w.of a wave of a certain frequency varies directly as the velocity. v, of the wave. W = 60 ft when v= 15 ft/s. Find w when v = 3 ft/s.

Answer 1

EXPLANATION

First we need to find the direct variation function:

$w=k\cdot\nu$

Then we need to use the given information λ=60 v=15 and write the equation:

$60=k\cdot15$

Dividing both sides by 15:

$\frac{60}{15}=k$

Simplifying:

$4=k$

So, the function is:

$w=4\cdot\nu$

Now, we use this function to find w when v=3:

$w=4\cdot3=12ft$

The wavelength is 12ft