Does Fermat’s principle of least time apply to refraction and reflection? Does Fermat’s principle of least time apply to refraction and reflection? (A) It does not apply to either reflection or refraction. (B) It applies both to refraction and reflection . (C) It applies only to reflection. (D) It applies only to refraction.

A 4.00-m-long pole stands vertically in a freshwater lake having a depth of 2.00 m. The Sun is 40.0° above the horizontal. Determine the length of the pole’s shadow on the bottom of the lake.

The end of a solid glass rod of refractive index 1.50 is polished to have the shape of a hemispherical surface of radius 1.0 cm. A small object is placed in air (refractive index 1.00) on the axis 5.0 cm to the left of the vertex. Determine the position of the image.

(i) An object is plated at a position p f from a concave mirror as shown in Figure CQ39.12a, where f is the focal length of the mirror. In a finite time interval, the object is moved to the right to a position at the focal point F of the mirror. Show that the image of the object moves at a speed greater than the speed of light. (ii) A laser pointer is suspended in a horizontal plane and set into rapid rotation as shown in Figure CQ39 12b. Show that the spot of light it produces on a distant screen can move across the screen at a speed greater than the speed of light. (If you carry out this experiment. make sure the direct laser light cannot enter a person's eyes.) (iii) Argue that the experiments in parts (i) and (ii) do not invalidate the principle that no material, no energy, and no information can move faster than light moves in a vacuum. Figure CQ39.12

KEY TERMS 1. reflection (7.1) 2. ray 3. law of reflection 4. specular reflection 5. diffuse reflection 6. refraction (7.2) 7. index of refraction 8. total internal reflection 9. dispersion 10. focal length (7.3) 11. concave (converging) mirror 12. convex (diverging) mirror 13. real image 14. virtual image 15. converging lens (7.4) 16. diverging lens 17. polarization (7.5) 18. linearly polarized light 19. diffraction (7.6) 20. principle of superposition 21. constructive interference 22. destructive interference For each of the following items, fill in the number of the appropriate Key Term from the preceding list. h. _____ A change in the direction of light at a surface

Curved glassair interfaces like those observed in an empty shot glass make it possible for total internal reflection to occur at the shot glasss internal surface. Consider a glass cylinder (n = 1.54) with an outer radius of 2.50 cm and an inner radius of 2.00 cm as shown in Figure P38.105. Find the minimum angle i such that there is total internal reflection at the inner surface of the shot glass. FIGURE P38.105 Problems 105 and 106.

An object of height 3 cm is placed at a distance of 25 cm in front of a converging lens of focal length 20 cm, to be referred to as the first lens. Behind the lens there is another converging lens of focal length 20 cm placed 10 cm from the first lens. There is a concave mirror of focal length 15 cm placed 50 cm from the second lens. Find the location, orientation, and size of the final image.

Light passes from a material with index of refraction 1.3 into one with index of refraction 1.2. Compared with the incident ray, what happens to the refracted ray? (a) It bends toward the normal. (b) It is undeflected. (c) It bends away from the normal.

For specular reflection, what is the situation with an angle of incidence of (a) 0 and (b) 90?

An observer to the right of the mirror-lens combination shown in Figure P36.89 (not to scale) sees two real images that are the same size and in the same location. One image is upright, and the other is inverted. Both images are 1.50 times larger than the object. The lens has a focal length of 10.0 cm. The lens and mirror are separated by 40.0 cm. Determine the focal length of the mirror.