1. Which of the Following Is NOT True for Electromagnetic Waves

1. Which of the following is NOT true for electromagnetic waves (a) they consist of changing electric and magnetic fields (b) they travel at different speeds in vacuum, depending on their frequency (c) they transport energy (d) they transport momentum (e) they can be reflected 2. An electromagnetic wave is generated by (a) any moving charge (b) any accelerating charge (c) only a charge with changing acceleration (d) only a charge moving in a circle (e) only a charge moving in a straight line 3. Linearly polarized light is incident on a sheet of polarizing material. The angle between the transmission axis and the incident axis light is 52o. What percentage of the incident intensity is transmitted? (a) 38% (b) 43 % (c) 52 % (d) 62 % (e) 79 % 4. A clear sheet of Polaroid is placed on top of a similar sheet so that their polarizing axes make an angle of 30o with each other. The ratio of the intensity of emerging light to incident unpolarized light is (a) 1:4 (b) 1:3 (c) 1:2 (d) 3:4 (e) 3:8 5. As light goes from one medium to another, it is bent away from the normal. Then (a) the speed of the light has increased (b) dispersion must occur (c) no change in speed has occurred (d) the second medium has a higher index of refraction than the first (e) refraction has not occurred because refraction means a bending toward the normal 6. The critical angle for total internal reflection at a diamond-air interface is 25o. Suppose light is incident at an angle  with the normal. Total internal reflection will occur if the incident medium is (a) air and = 25o (b) air and  > 25o (c) air and < 25o (d) diamond and  > 25o (e) diamond and  < 25o 7. An object is 2 m in front of a plane mirror. Its image is (a) virtual, inverted, and 2 m behind the mirror (b) virtual, inverted, and 2 m in front the mirror (c) virtual, erect, and 2 m behind the mirror (d) real, erect, and 2 m behind the mirror (e) none of the above 8. A light bulb burns in front of the center of a 40 cm wide plane mirror that is hung vertically on a wall. A man walks in front of the mirror along a line that is parallel to the mirror and twice as far from it as the bulb. The greatest distance he can walk and still see the image of the bulb is (a) 20 cm (b) 40 cm (c) 60 cm (d) 80 cm (e) 120 cm 9. An erect object is in front of a convex mirror a distance greater than the focal length. The image is (a) real, inverted and smaller than the object (b) virtual, inverted, and larger than the object (c) real, inverted and larger than the object (d) real, erect and larger than the object (e) virtual, erect, and smaller than the object 10. As an object is moved from a distance location toward the center of curvature of a concave mirror its image (a) remains virtual and becomes smaller (b) remains virtual and becomes larger (c) remains real and becomes smaller (d) remains real and becomes larger (e) changes from real to virtual 11. An erect object is located on the central axis of a spherical mirror. The magnification is -3. This means (a) its image is real, inverted and on the same side of the mirror (b) its image is virtual, erect and on the opposite side of the mirror (c) its image is real, erect and on the same side of the mirror (d) its image is real, inverted and on the opposite side of the mirror (e) its image is virtual, inverted and on the opposite side of the mirror 12. An object is placed at the focal point of a converging lens of focal length f. The image distance is (a) f (b) 2f (c) 1/f (d) 2/f (e) infinity 13. Rachel has a far point of 5 m. Which statement concerning Rachel’s vision is true? (a) She has a normal vision. (b) She is nearsighted and requires diverging lenses to correct her vision. (c) She is nearsighted and requires converging lenses to correct her vision. (d) She is farsighted and requires diverging lenses to correct her vision. (e) She is farsighted and requires converging lenses to correct her vision. 14. An erect object is 2f in front of a converging lens of focal length f. The image is (a) real, inverted, magnified (b) real, erect, same size (c) real, inverted, same size (d) virtual, inverted, reduced (e) real, inverted, reduced 15. When an object is placed 20 cm from a diverging lens, a reduced image is formed. Which one of the following statements is necessarily true? (a) the image is inverted (b) the image could be real (c) the image distance must be greater than 20 cm (d) the focal length of the lens may be less than 20 cm (e) none of the above