12.5, 12.7 textbook questions PDF

Preview

Summary

Download 12.5, 12.7 textbook questions PDF

Description

12.5 textbook questions 1. The index of refraction must decrease across the boundary in the direction of light refraction. The angle of incidence of the light ray must exceed the critical angle of the interface. Ray must travel from denser to rarer medium. 2. Total internal reflection happens only as light passes more slowly through the first medium than through the second, rather than the other way around, and as light travels quickly through the second medium, the beam speeds up and bends away from the angle of incidence. External reflection occurs where the angle of incidence is greater than the angle of reflection. This cannot happen the other way around because the refracted ray bends away from the usual only as light enters a less dense medium.

3. A) 23.7: Light rays will be refracted B) 34.7: Light rays will be internally reflected C) 53.4: Light rays will be internally reflected D)31.5: Light rays will be refracted 5. The angle of the incident ray must be greater than the critical angle for the light to reflect internally. This means that the smaller the critical angle of a medium, the more it has the ability to reflect light internally as compared to a medium with a large critical angle.

12.7 textbook questions 1 Apparent depth – is the depth an object APPEARS to be but is not really. It is an illusion created by the refraction of light as it moves between water and air. 2 If I really want to scoop a fish out of water, I will need to aim BELOW where I see it. Refraction makes the fish appear to be HIGHER in the water than it really is. (You can use a diagram to explain here too – like on page 535 3 Index of refraction decreases (gets lower) as air warms up. That means cold air has a higher index of refraction and light travels more slowly in cold air than warm air. (light speeds up as it travels through warm up) 4 The water mirage is really you seeing an image of the sky. 5 If violet light refracts more, than the ‘n’ value or index of refraction is greater for violet light than red light. 6 Rainbows occur because of refraction (light refracts as it enters AND leaves the water droplet), dispersion (ROYGBIV refracts differently, and thus white light separates into the rainbow colors) and T.I.R. (because light totally internally reflects inside the water droplet). 7 Different colors in white light (ROYGBIV) have different speeds in water and this allows for the colors to refract different amounts. This different amount of bending separates the colors. Separating the colors is what makes the rainbow. So…if the different colors didn’t travel at different speeds in water, there would be NO rainbow....