Question

FM radio broadcasts at 800 kHz. What wavelength does this correspond to?
(1 kHz $={10}^3$ Hz)

• A. $375$ $m$
• B. $330$ $cm$
• C. $3.03$$\times {10}^{-3}m$
• D. $330$ $m$

Answer 1

The correct option is A $375$ $m$

Wavelength of light is given by:
$\lambda$ = $\frac{c}{\nu }$
where $c=$ speed of light
and $\nu =$ frequency

We know that,
$c=$ $3\times {10}^{8}m/s$
$\nu =$ 800 kHz $=8\times {10}^5$ Hz
Substituting the values,
$\lambda$ = $\frac{3\times {10}^8}{8\times {10}^5}$
$\lambda =375$ $m$