71. A light ray enters a rectangular block of plastic at an angle & 1 ! 45.0° and emerges at an angle & 2 ! 76.0°, as shown in Figure P35.71. (a) Determine the index of refraction of the plastic. (b) If the light ray enters the plastic at a point L ! 50.0 cm from the bottom edge, how long does it take the light ray to travel through the plastic?

A light ray travels through three parallel slabs having different indices of refraction as in Figure CQ22.3. The rays shown are only the refracted rays. Rank the materials according to the size of their indices of refraction, from largest to smallest. Figure CQ22.3 ne 726 "a

A light beam is traveling through an unknown substance. When it strikes a boundary between that substance and the air (?air≈1),(nair≈1), the angle of reflection is 25.0∘25.0∘ and the angle of refraction is 47.0∘.47.0∘. What is the index of refraction ?n of the substance?

The reflecting surfaces of two intersecting flatmirrors are at an angle of 66◦, as shown inthe figure. A light ray strikes the horizontalmirror at an angle of 48◦ with respect to themirror’s surface. Calculate the angle φ.Answer in units of ◦.

A ray of light is incident at angle ?θ = 59° on the side of two stacked transparent blocks. The bottom block has index of refraction ?1n1 = 1.41. The ray enters the top block at angle ?ϕ = 40.6°. What is the index of refraction ?2n2 of the top block? Note: Angles may not be drawn to scale.

. A plastic-coated window consists of Perspex and glass. At the Perspex to glassinterface the angle of refraction is 30.00. and the angle of incidence is 20.00. Ifthe refractive index of the glass is 1.75, what is the refractive index of thePerspex?

An object is placed 9.50 cm in front of the cornea. (The cornea is thin ans has approximately parallel sides so that the reflection that occurs as light travels from air to cornea to aqueous humor is essentially the same as though the aqueous humor were directly in contact with the air. The aqueous humor has index of refraction n = 1.34 and the radius of curvature of cornea is 7.8 mm.) (a) What is the image distance for the image formed by the cornea alone? (b) The image formed by the cornea serves as an object for the lens. Treat the lens as a thin lens 4 mm behind the cornea. Find the optical power of the lens necessary to form an image on the retina, 23 mm from the center of the lens.

A student stands dsub0=2.4 m in front of a floor-to-ceiling mirror. Her eyes are hsube=1.53 m above the floor and she holds a flashlight at a distance hsubf=.55 m above the floor. Calculate the angle in degrees that the flashlight makes with respect to the floor if the light is reflected into her eyes.