Long Wavelength Short Wavelength

Physics Optics Packet

1. Draw a schematic showing the electromagnetic spectrum. Label the directions of longer wavelength, higher frequency, and higher energy per photon. Label the following regions of the spectrum: visible light, IR, UV, x-rays, radio waves, gamma rays.

Long wavelength short wavelength Radio, IR, visible, UV, x-rays, gamma Low frequency high frequency Low energy high energy

2. Fill in:

Type of Wavelength Frequency Energy per Visible or invisible photon photon radio 1m 3X108 2X10-25 i radio 300m 1MHz 6.626X10- i 28J gamma 2X10-17M 1.51X1025 .00000001J i visible 500nm 6X1014 4X10-19J v .00000001m 3X1016 2X10-17J i

3. For each, tell which property of light is exhibited: A. Light bounces off a surface, creating glare reflection B. Light waves are bent when they pass from air to water refraction C. Light waves from a flash light are dissipated when the flashlight is used during the day. interference D. Light waves pass through a small gap in some material and spread out behind the gap diffraction E. Light from some stars appears shifted to lower frequencies when viewed from the earth Doppler effect

4. Give the term that fits the definition: A. The distance between crest to crest or trough to trough on a wave wavelength B. The number of wavelengths that pass a point in one second frequency C. The time it takes for one wavelength to pass a point period D. Waves that vibrate along a single plane polarized

5. Circle one A. Higher frequency: visible IR B. Longer wavelength: UV radio C. Higher energy per photon: red light green light

Physics Optics 2

1. Write the law of refraction: ni sin(angle of incidence) = nr sin(angle of refraction)

2. Calculate the speed of light in the following materials: A. Diamond 1.24X108

B. Flint glass 1.81X108m/s C. Crown glass 2X108m/s D. Water 2.26X108m/s E. Air 2.999X108m/s 3. The speed of light through a material is 1.5X108m/s. Find the index of refraction of the material. 2

4. Trout fishermen often approach a body of water by crawling or walking on their knees. Explain why using your knowledge of refraction. You can draw a picture to help.

Due to refraction the fish can see the angler before the angler can see the fish.

5. Write Snell’s Law: ni sin(angle of incidence) = nr sin(angle of refraction)

6. Use Snell’s Law to predict the angle of refraction as light passes from air into diamond. The light strikes the diamond at an angle of 30 degrees from the normal. 11.9 degrees 7. Draw a picture of light passing from air into crown glass and back into air. The light strikes the crown glass at an angle of 60 degrees from the normal. Calculate and label all the angles involved. 35.3 degrees, 60 degrees back in air

8. Draw a prism and explain what property of light accounts for the white light entering the prism being split into different colors. Refraction causes dispersion because each frequency of light has a slightly different speed through glass

Physics Optics 3

On a Separate Sheet:

1. Name and draw pictures of the two types of lenses. Converging, diverging 2. Draw light rays entering and exiting both types of lens. Label the focal point and focal length on both types of lens.

3. Draw light rays entering and exiting both types of lenses. For each type of lens show what happens to the following three types of rays: parallel, central, focal.

4. Describe the difference between a real image and a virtual image. Real can be focused on a surface, virtual cannot 5. Which type of lens can produce which types of image? Convex either, concave virtual only 6. Write the thin lens equation. Also write the sign conventions for lenses. 1/f = 1/p + 1/q 7. Use the thin lens equation for the following problems: A. A magnifying glass with focal length .01m has an object .05m in front of it. Where is the image? B. The magnifying glass from problem A is forming an image .03m behind it. Where is the object?

8. The magnification for a lens is 3. How far is the object from the lens if the image is . 06m from the lens?

9. Draw a picture of a converging lens forming an image when the object is 60cm away from a lens whose focal length is 20cm. Is the image smaller or larger than the object? Is the image inverted or upright? Is the image real or virtual? 10. Draw a picture showing a lens and the chromatic aberration of this lens.

11. Complete the following table:

From (medium) To (medium) Angle of incidence Angle of refraction Air Water 30 degrees 22.1 Water Diamond Domain error, skip 35 degrees Crown glass Flint glass 20 degrees 22.24 Air Flint glass 45 degrees 28.13 Water Cubic zirconia 5 degrees 2.27 Air Water 41.7 30 degrees

Physics Optics 4

1. Draw the two types of curved mirrors and show light rays hitting the mirrors and reflecting from them.

2. Draw an object in front of a plane mirror and label the following: object height, image height, distance of object from mirror, distance of image from mirror, eye looking at the mirror.

3. Draw a concave mirror and show the center of curvature and the focal point. 4. Draw a convex mirror and show the center of curvature and the focal point.

5. Which type of mirror would be used for? A. forming a real image concave B. helping to see around things convex C. magnifying objects concave D. focusing the sun’s rays on a point concave E. making objects look smaller convex F. forming a virtual image concave, convex, or plane 6. Draw a concave mirror with an object in front of it. Label the following: center of curvature, focal point, object, image. Say whether the image is real or virtual, upright or inverted. Image depends on how far from the mirror it is

7. Draw a convex mirror with an object in front of it. Label the following: center of curvature, focal point, object, image. Say whether the image is real or virtual, upright or inverted. Upright, virtual

8. A spherical mirror with focal length 1m has an object .5m in front of it. Where is the image? -1m

9. A spherical mirror has an object placed in front of it. The object is .5m tall and the magnification of the mirror is -.5. How tall is the image? -.25m

10. A spherical mirror has an object 3m away from it. The image distance is -1m. Find the magnification of the mirror. .33

Physics Optics 5

1. In what medium is the speed of light highest? vacuum

2. Guess the relative speed of light through these media: air, glass, water. Air>water>glass

3. A student wants to be able to make light turn around a 90 degree bend. How could they best do this? Give another way they could do this that would also work. 2 mirrors at 45 degrees or two prisms doing total internal reflection

4. Draw cartoons for the following processes: refraction, reflection, polarization, total internal reflection.

5. Draw the following types of optical device interacting with light: convex lens, concave lens, converging lens, diverging lens, convex mirror, concave mirror. How can you get away with only drawing four drawings instead of six? Convex lenses are converging and concave lenses are diverging

6. How much time would it take for light to reach the earth from a star that is 10 light years away? How much time would it take for light to go from the star, then bounce off a mirror on earth and go back to the star? How long would each process take if the light had to go through diamond instead of space? How far is the star from us in meters? 10 year, 20 years, 24.2 years, 48.4 years, 9.46X1016m

7. Draw a cartoon of light going from air to glass to water to glass and back to air.

8. Tell whether each lens will cause either convergence or divergence of light rays. Con, con, con, di, di, di

9. What two properties of light allow it to be polarized? It is a wave and it is transverse

10. When a light wave passes into a medium other than a vacuum the speed changes. The frequency does not change. Does the wavelength change? If you think it does calculate the wavelength of 550nm light in the following media: diamond, water, glass with n = 1.5. 227, 414, 367

11. This cartoon shows what kind of wave? Longitudinal

Physics Optics Practice

1. A ray of light hits a plane mirror at an angle of 35 degrees from the normal. What angel does it bounce off at? 35 degrees from the normal

2. What kind of mirror can we use to make a solar oven? What kind of mirror would we not use? Concave, convex

3. A ray of light travels through a vacuum then strikes glass that has an index of refraction of 1.5. The ray impacts the glass at an angle of 40 degrees. What is the angle at which the light ray travels through the glass? 25.4 degrees

4. The light ray in problem 3 travels all the way through the glass and propagates through water on the other side of the glass. The index of refraction for water is 1.33. Find the angle at which the light ray travels through the water. 28.9 degrees

5. Label the incident ray, refracted ray and reflected ray. Assume that n1 is air. Use a protractor and Snell’s Law to find the value of n2. Your results may vary depending upon your skill with a protractor.

What types of optical device does this camera use? What purposes are the devices serving? 2 convex lenses and 1 concave lens Focusing and avoiding chromatic aberration

The diagram above shows what type of lens? What two phenomena are occurring in the diagram? Convex lens, refraction and chromatic aberration

8. The diagram above shows what type of optical device? How does the device work and what can it be used for? Concave mirror, converges light, magnifies things.

What type of optical device is shown above? What does the device do to light rays? Describe the image formed by the device as larger or smaller than the object, real or virtual, and upright or inverted. Converges light rays, forms a larger inverted real image

What types of optical device are shown above? Why does the lower setup use two devices and what problem is being corrected? Lenses. The bottom has two lenses to correct the chromatic aberration that occurs at the top

11. Tell what types of optical devices are being used above. Describe what they do and what types of images they are forming. Top: convex (converging) len, converges light, forms an inverted real image Bottom: concave (diverging) lens, forms an upright virtual image

What process is occurring above? Diffraction and interfence

The diagram above shows three eyes. What type of lens would be used to correct the vision in each type of eye (if it needs correcting)? Draw a diagram showing how the lens would correct the vision problem and state whether the person with the eye would be far or near sighted. A = good vision B = convex lens C = concave lens