Phys 4, Section 2                                                                 May 7, 2002

λ = h/p     f^# = f/D         d sin θ_m = mλ (bright)         a sin θ_m = mλ (dark)
p = mv         λ = λ_o/n         sin θ = 1.22 λ/D         1 eV = 1.6 H 10^-19 J     K = mv²/2
E = hv         K = hv - φ         υ = vλ         k = 2π/λ             2π rad = 360^o  
h = 6.63 × 10^-34 J·s    1/f = (n-1)(1/R₁ - 1/R₂)     1/f = 1/s + 1/s'         m = -s'/s
M = θ'/Θ         f = R/2        n₁/s + n₂/s' = (n₂ - n₁)/R     
M = f₁/f₂     M = (25 s₁')/(f₁f₂)     M = 25/f_cm        F = kq₁q₂/r²     U = kq₁q₂/r     
V = W/q         E = kq/r²
                 Δt = γΔt_o             L = L_o/γ             m = γm_o
Δx Δp ≥ h/2π         L_n = mv_nr_n = nh/2π         |e^-| = 1.6 × 10^-19 C 
k = 9 × 10⁹ N·m²/C²

1. What type of mirror has similar imaging characteristics as a double convex lens?
A) concave             B) convex             C) plane

2. An object 12 cm high is located on the optic axis of a lens with a +40 cm focal
length. If the object is 100 cm in front of the lens, how large is the image?
A) 2         B) 4         C) 6         D) 8         E) 10                                         cm

3. What maximum set of the following vectors are always in a single plane when a
ray of light hits an interface?
A) refracted and reflected                 B) incident and refracted         
C) incident, reflected, refracted         D) incident, refracted, normal    
E) incident, reflected, refracted, and normal

4. The left end of a long glass rod 6.00 cm in diameter has a convex hemispherical
surface 3.00 cm in radius. The refractive index of the glass is 1.60. Determine the
position of the image is an object is placed in air on the axis of the rod 12 cm from
the left end.
A) 5.8         B) 13.7         C) 22.8         D) 36.1         E) 44.9                         cm

5. The Yerkes refracting telescope of the University of Chicago has an objective
1.02 m in diameter with an f-number of 19.0. What is its focal length?
A) 2.04         B) 4.2         C) 9.1         D) 12.5             E) 19.4                         m

6. The focal length of the eyepiece of a certain microscope is 18.0 mm. The focal
length of the objective is 8.00 mm. The distance between objective and eyepiece
is 19.7 cm. The final image formed by the eyepiece is at infinity. What is the
approximate overall angular magnification of the microscope?
A) 100         B) 200         C) 300         D) 400             E) 500

7. Who first devised the famous two-slit experiment?
A) Foucault         B) Newton         C) Maxwell         D) Young         E) Thomson

8. What is the thinnest film of a coating with n = 1.42 on glass (n = 1.52) for
which destructive interference occurs for light with λ_o = 650 nm reflecting off the
film into air?
A) 114         B) 227         C) 336         D) 489         E) 511                         nm

9. In the Newton's rings measurement a plano-convex glass lens is placed (convex
side down) on a flat glass plate. As seen by reflected light, will the center contact
point be bright or dark?
A) bright                 B) dark                     C) medium

10. Light with λ = 632.8 nm passes through a narrow slit and produces a diffraction
pattern on a screen 6.0 m away. If the distance between the centers of the first
minima outside each side of the central bright fringe is 32 mm, how wide is the
slit?
A) 0.06         B) 0.12         C) 0.18         D) 0.24         E) 0.30                 mm

11. A child sitting next to a window is spinning a toy while riding on a high-speed
spaceship. The top will appear to spin more rapidly to an observer who is
A) on the spaceship         B) on earth watching the spaceship go by
C) both observers will see the top with the same spin rate.

12. When is there a phase change of half-a-wavelength upon reflection at an
interface between media of different indices of refraction?
A) high to low             B) low to high         C) both cases         D) neither case

13. If you can read the bottom row of your doctor's eye chart, your eye has a
resolving power of one arc-minute, equal to 1/60 of a degree. To what effective
diameter of your eye's optical system does this correspond? (Use λ = 550 nm)
A) 0.6         B) 1.8         C) 2.3         D) 3.7         E) 4.2                         mm

14. Which principle says that for large quantum numbers (n → ∞ ), quantum
mechanics and classical mechanics give the same result?
A) uncertainty     B) complementarity     C) correspondence     D) none of these

15. The predominant wavelength emitted by an ultraviolet lamp is 248 nm. If the
total power emitted at this wavelength is 12.0 W, how many photons are emitted
per second?
A) 1.0         B) 1.5         C) 2.0         D) 2.5             E) 3.0                 × 10¹⁹ /s

16. A 4.78 MeV alpha particle (q = 2|e^-|, m = 6.64 × 10^-27 kg) makes a head-on
collision with a massive uranium nucleus (q = 92|e^-|). What is the distance of
closest approach of the alpha to the center of the nucleus?
A) 1.1         B) 2.2         C) 3.3         D) 4.4         E) 5.5                     × 10^-14 m

Last modified on May 08, 2002