Question

At which angle of incidence, does the angle of deviation typically reach a minimum for a triangular prism?

Options

• 30 degree

• 45 degree

• 60 degree

• It depends on the specific prism material

Answer 1

60 degree

Explanation:

The angle of deviation typically reaches a minimum for a triangular prism when the angle of incidence is equal to the prism's apex angle. In this case, the prism has an apex angle of 60°. So, for a triangular prism with 60° apex, the angle of deviation will be minimised when the angle of incidence is also 60°.