For light of wavelength 589 nm, calculate the critical angles for the following substances when surrounded by air. 43.3 Your response differs from the correct answer by more than 10%. Double check your calculations. 37.0 Your response differs from the correct answer by more than 10%. Double check your calculations. water fluorite 31.3 flint glass Your response differs from the correct answer by more than 10%. Double check your calculations.

A mode-locked laser has a linewidth of 100nm at a center wavelength 1050nm. Assume the pulse shape is hyberbolic secant and it is transform limited. What is the pulse width (in fs)? (round all answers to 1 sig. fig. after decimal point)   a.116.0   b.11.6   c.5.8   d.58.0   e.100.0

The figure below depicts spectral reflectance measurements for three different materials:  a green leaf from a healthy plant, a sheet of shiny blue paper, and the palm of a human hand.  The measurements are labeled 1 (black line), 2 (red line), and 3 (blue line).  Match the measurements to the most appropriate material type

In relation to x-ray imaging, which of the following statements is true? Choose one answer.   a. The linear attenuation coefficient of a material is directly proportional to its half value thickness.     b. For clinically useful x-rays, lead has a greater half value thickness than soft tissue.     c. The intensity of an x-ray beam decreases exponentially as it passes through tissue.     d. The intensity of an x-ray beam increases exponentially as it passes through tissue.     e. Good contrast media are generally poor absorbers of X-rays.     and Why??