Sydney wanted to color her hair from home so she signed up for an online service that sent hair color directly to her. The service required information about the thickness of Sydney's hair to mix the color properly. They only wanted to know if it was fine, medium, or thick, but being an astute student of physics, Sydney knew she could be more precise than that! She shone a red laser pointer with a wavelength of 670 nm through a single strand of hair and a diffraction pattern appeared on the wall 1.85 m away. a) Explain why this fringe pattern appears and how it confirms the wave nature of light. What would you predict the image on the screen to look like if light were a particle instead? b) What is the thickness of Sydney's strand of hair? Explain which formula is best to use here and why?

Sydney wanted to color her hair from home so she signed up for an online service that sent hair color directly to her. The service required information about the thickness of Sydney's hair to mix the color properly. They only wanted to know if it was fine, medium, or thick, but being an astute student of physics, Sydney knew she could be more precise than that! She shone a red laser pointer with a wavelength of 670 nm through a single strand of hair and a diffraction pattern appeared on the wall 1.85 m away. a) Explain why this fringe pattern appears and how it confirms the wave nature of light. What would you predict the image on the screen to look like if light were a particle instead? b) What is the thickness of Sydney's strand of hair? Explain which formula is best to use here and why?