1. b. A diverging lens refracts rays away from the optical axis, so the rays will travel farther down the axis before converging.

2. a. Because the shutter speed doesn’t change, the f-number must remain unchanged. The f-number is $f/D$, so increasing $f$ requires increasing $D\text{.}$

3. a. A magnifier is a converging lens. Converging lenses are used to correct hyperopia.

4. b. The objective forms a real image, but the image of the eyepiece—a magnifier—is a virtual image inside the microscope that the eye can view.

5. $w{}_A>w{}_D>w{}_B=w{}_C$. The spot size is proportional to $f/D$.

1.

2. $s{\prime }_2=49\text{cm, }h{\prime }_2=4.6\text{cm}$

3.

2. $s{\prime }_2=-30\text{cm, }h{\prime }_2=6.0\text{cm}$

5. 10 cm

7. 3.0 mm

9. 1/250 s

11.

1. Myopia

2. 100 cm

13. 3.0

15. 5.0 cm

17. $13\mu \text{m}$

19. 6.0 mm

21. $0.4\text{°}$

23. 1600 nm

25. 55 km

27. 2.0 cm, right; 6.0 cm, right

29.

1. $f_2+f_1$

2. ${\displaystyle \frac{f_2}{\left|f_1\right|}}{w}_1$

31. 16 cm placed 80 cm from screen

33. 23 cm

35. 3.5 m

37.

1. $+4.5\text{D lens}$

2. 1.5

3. 0.56 m

39.

1. 0.225 mm

2. $480\mu \text{m}$

41. $1.0\text{°}$

43. 15 km

45.

1. $1.0\times {10}^{11}\text{km}$

2. 130

47.

2. $1.574$

49.

2. $\text{Δ}{n}_2=\frac{1}{2}\text{Δ}{n}_1$

3. Crown converging, flint diverging

4. 4.18 cm