Question

"Critical Angle is 40°" What is meant by this?

Answer 1

Answer:

The critical angle is 40°at the interface from plastic to air. Figure 11 shows a light ray is incident on the top surface of the plastic block. Draw on Fig. 11 the ray path inside the plastic block until it emerges from the block. All the refraction and reflection angles should be drawn to scale using a protractor 15 Air Plastic Figure 11