### Short Answer

## 17.1 Understanding Diffraction and Interference

What is the longest wavelength of light passing through a single slit of width 1.20 μm for which there is a first-order minimum?

- 1.04 µm
- 0.849 µm
- 0.600 µm
- 2.40 µm

## 17.2 Applications of Diffraction, Interference, and Coherence

Suppose pure-wavelength light falls on a diffraction grating. What happens to the interference pattern if the same light falls on a grating that has more lines per centimeter?

- The bands will spread farther from the central maximum.
- The bands will come closer to the central maximum.
- The bands will not spread farther from the first maximum.
- The bands will come closer to the first maximum.

How many lines per centimeter are there on a diffraction grating that gives a first-order maximum for 473 nm blue light at an angle of 25.0°?

- 529,000 lines/cm
- 50,000 lines/cm
- 851 lines/cm
- 8,934 lines/cm

What is the distance between lines on a diffraction grating that produces a second-order maximum for 760-nm red light at an angle of 60.0°?

- 2.28 × 10
^{4}nm - 3.29 × 10
^{2}nm - 2.53 × 10
^{1}nm - 1.76 × 10
^{3}nm