Physics

Problem

Which one of the following correctly gives the phase difference

\Delta\varphi

(in rad) corresponding to a path difference

\Delta x

for a sinusoidal wave of wavelength

\lambda

? a)

\displaystyle \Delta\varphi = \frac{\lambda}{2\pi\,\Delta x}

\displaystyle \Delta\varphi = \frac{360\,\Delta x}{\lambda}

\displaystyle \Delta\varphi = \frac{2\pi\,\Delta x}{\lambda}

\displaystyle \Delta\varphi = \frac{\pi\,\Delta x}{\lambda}