Question

What is the wavelength of the wave?

An infrared wave has a speed of 3 * 10^8 m/s and a time period of 2.67 * 10^-15 seconds.

Answer 1

I get `8*10^21` meters.

Explanation:

Well, we first need to find the frequency of the wave, that is,

`f=1/T`

• `T` is the period of the wave in seconds

And so,

`f=1/(2.67*10^-15 \ "s")`

`~~3.75*10^14 \ "s"^-1`

`=3.75*10^-14 \ "Hz"`

Now, we use the wavelength equation, which states that,

`lambda=v/f`

• `v` is the velocity of the wave in meters per second

• `f` is the frequency of the wave in hertz

So, plugging in the values, we get,

`lambda=(3*10^8 \ "m/s")/(3.75*10^-14 \ "Hz")`

`=(3*10^8 \ "m"color(red)cancelcolor(black)("s"^-1))/(3.75*10^-14color(red)cancelcolor(black)("s"^-1))`

`=8*10^21 \ "m"`