Final answer:
The statement is false; a light ray striking the surface of a glass slab normally does not deviate from its path since there is no angle to cause refraction at the boundary.
Step-by-step explanation:
The statement that a light ray striking the surface of a glass slab normally will deviate from its path is false. When a light ray enters a new medium perpendicular to the surface, as in this case normally (at a 90-degree angle), it will not bend or deviate from its path. This is because there is no angle of incidence, and therefore no refraction occurs due to the change in medium. However, when a light ray enters glass at any other angle, it will bend towards the normal due to glass having a higher index of refraction than air. The process by which this bending occurs is known as refraction, and it is distinct from reflection, wherein light bounces from the surface rather than being bent by it.