Question

3. 0/4 points Previous Answers An FM station broadcasts classical music at 88.8 MHz (megahertz, or 106 Hz). Find the wavelength (in m, nm, and A) of these radio waves. 0 266 Your response differs from the correct answer by more than 10%. Double check your calculations, m nm 4. -14 points A particular x-ray has a wavelength of 1.6 A. Calculate the energy (in)) of one photon of this radiation Submit Answer
need answer to 3 & 4 please

Answer 1

3.

We have

Frequency = 88.8 MHz = 88.8 $\times$ 10⁶ Hz

Now the formula of wavelength

wavelength = Speed of light / frequency

where speed of light c = 3.0 $\times$ 10⁸ m/s

so

Wavelength $\lambda$ = 3.0 $\times$ 10⁸ m/s / 88.8 $\times$ 10⁶ Hz = 3.78 m

to convert wavelength from m to nm

we know that

1 m = 1 $\times$ 10⁹ nm

so

Wavelength = 3.78 $\times$ 10⁹ nm

Also

1 m = 1 $\times$ 10¹⁰ A⁰   

then

Wavelength = 3.78 $\times$ 10¹⁰ A⁰

4.

we have

wavelength = $\lambda$ = 1.6 A⁰ = 1.6 $\times$ 10^-10 m

Energy E = hc / $\lambda$

where h = Plancks constant = 6.626 $\times$ 10^-34 J.s

c = speed of light = 3.0 $\times$ 10⁸ m/s

So

Energy = 6.626 $\times$ 10^-34 J.s $\times$ 3.0 $\times$ 10⁸ m/s / 1.6 $\times$ 10^-10 m

= 12.42 $\times$ 10^-16 J