Question

Wavelength of light of frequency $100$ $Hz$ is,

• A. $4\times {10}^{6}m$
• B. $3\times {10}^{6}m$
• C. $2\times {10}^{6}m$
• D. $5\times {10}^{-5}m$

Answer 1

The correct option is B $3\times {10}^{6}m$

Speed of light $=3\times {10}^{8}m/s$
frequency$=100Hz$
we know that, speed = frequency $\times$ wavelength

$\frac{3\times {10}^8}{100}=$ wavelength
$\therefore$ wavelength $=3\times {10}^{6}m$