212 - Problem Set #11

Physics 212 Fall 2008 Problem Set #11 Read: 23.2, 23.3, 24.4, 25.1. Due Monday, November 10th. 1)

2)

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5)

The distance from a converging lens to its focal points is 40 cm. An object is placed 20 cm from the lens. a) Draw a Light Ray Diagram for this situation, b) Calculate the image distance and the magnification, c) Describe the state of the image (real/virtual, upright/inverted, bigger/smaller). The distance from a diverging lens to its focal points is 20 cm. An object is placed 30 cm from the lens. a) Draw a Light Ray Diagram for this situation, b) Calculate the image distance and the magnification, c) Describe the state of the image (real/virtual, upright/inverted, bigger/smaller). Skid is slightly nearsighted. He has far points of 5 m from the right eye and 6.5 m from the left eye. Skid goes to the optometrist for contact lens. What prescription does the doctor write? (i.e. what is the power of each corrective lens?) In the early days of the Charming Beggars, Skid used a concave makeup mirror to apply black eyeliner (very 80s) before a gig. The mirror was designed in such a way that a person 25 cm in front of the mirror would see an upright image magnified by a factor of two. What is the radius of curvature of Skid’s mirror?

polarized parallel to the surface of the glass. What is the index of refraction of the glass?

7)Unpolarized light of intensity 1.1 W/m

is incident on a polarizer. (a) What is the intensity of the light that leaves the polarizer?, (b) If an analyzer is set at an angle of 75° with respect to the polarizer, what is the intensity of the light that leaves the analyzer?

8)

Two identical diverging lenses are placed 16 cm apart. The focal points are located 8 cm away from the lenses. An object is placed 4 cm to the left of the lens on the left. Calculate the final image distance relative to the right lens.

9)

Two coherent sources emit waves that have a wavelength of 0.44 m. Determine whether constructive or destructive interference occurs at a point whose distances from the two sources are as follows: (a) 1.32 and 3.08; (b) 2.67 and 3.33 m; (c) 2.20 and 3.74 m; (d) 1.10 ad 4.18 m.

10)Light of wavelength 630 nm is incident on a double-slit. The slit separation is 5.3 x 10-5 m. Find the angles that locate the (a) first order, (b) second order, and (c) third order bright fringes on a wall 10 m away.

A convex mirror with a radius of curvature of 10 cm creates a virtual image that is one-third the size of the object. Where is the object located?

ANSWERS: 1) b) -40 cm, 2 2) b) -12 cm, 0.4 3) Right: –0.2 diopters, Left: –0.15 diopters 4) 1 m 5) 10 cm 6) 1.52

7)a)0.55 W/m b)0.037 W/m 8) -5.6 cm 2

2

9) a) Constructive 10) a) 0.68°

6)Light is reflected from a glass television screen.

When the

angle of incidence is 56.7°, the reflected light is completely

2

b)1.4° c) 2.0°