1. For a ray of light travelling from air to water (index of reflection of water is 1.33), if the incoming ray makes an angle of 50 degrees relative to the surface of the water at what angle relative to the surface will the ray travel in the water.

2. How long does it take light to travel through a 100 cm thick piece of clear polystyrene plastic (n=1.59)?

3. A red laser has a wavelength of 700 nm. what are the wavelength and frequency of this red light in water (n=1.33)

4. A person with 20/20 vision can see what an average individual can see on an eye chart when they are standing 20 feet away. An average individual can make out an 8.8 mm tall letter on an eyechart stamdimg 20 feet away. (2.54cm = 1 inch) What is the size of the image (in mm) that forms on the person's retina? assume that the eyeball has a radius of 1.2cm.

5. A 500 line/mm diffraction grating is illuminated by light of wavelenghth 510 nm. What is the angle of the m=2 diffraction pattern relative to the central bright spot?