Huygen's Principal: Practice Problem & Solution

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Huygen's Principal. Understanding the underlying formula is key to arriving at the correct answer below:

Wavefronts are surfaces of constant phase which are perpendicular to the direction of propagation. Since propagation is along the y-axis, the wavefront must be parallel to the x-z plane, represented by \(y =\text{ constant}\).