The net angle of deviation produced by the prism in the diagram shown below is ...............

0°

Reason — From the diagram, the light ray enters the prism through one refracting face, suffers total internal reflection at the base of the prism and finally emerges out through the other refracting face. The emergent ray is parallel to the incident ray and it travels in the same direction as the incident ray.

Since the emergent ray has not turned from the direction of the incident ray, the net angle of deviation produced by the prism is 0°.