In the Young's double slit experiment, the intensities at two points $P_1$ and $P_2$ on the screen are respectively $I_1$ and $I_2$. If $P_1$ is located at the center of a bright fringe and $P_2$ is located at a distance equal to a quarter of fringe width from $P_1$, then $I_1/I_2$ is :

Question

\[\begin {array} {1 1} (1)\;2 & \quad (2)\;1/2  \\ (3)\;4 & \quad (4)\;16 \end {array}\]