Question

Which of the following results in more energy in a wave ?

• A. a smaller wavelength
• B. a lower frequency
• C. a shallower amplitude
• D. a lower speed

Answer 1

Answer: (A)

The intensity $I$ of a wave is given by ,

$I=$Energy/(time$\times$area) ,

or energy=$I\times time\times area$ ,

thus we see that energy of a wave depends upon its intensity and intensity , $I\propto f^2$ (f=frequency) , and $f\propto 1/\lambda$ , therefore a smaller wavelength will result in more energy in a wave .

Besides that , energy associated with a wave of wavelength $\lambda$ is given by ,

$E=hc/\lambda$ ,

which also means that a smaller wavelength results in more energy .