Test On Monday

Question 1

What must an object do for you to see it?

Answer 1

Reflect light

Question 2

What type of reflection shows a clear image?

Answer 2

Regular reflection

Question 3

What type of reflection does a brick wall cause?

Answer 3

Diffuse reflection

Question 4

What is a material through which nearly all light passes?

Answer 4

Transparent

Question 5

What is a material that lets some light pass through?

Answer 5

Translucent

Question 6

What do we call materials that no light passes through?

Answer 6

Opaque

Question 7

What is white light a mixture of?

Answer 7

All visible wavelengths of the spectrum

Question 8

What do black objects do?

Answer 8

Absorb all colors and reflect little light

Question 9

What are the three primary colors of light?

Answer 9

• Red
• Blue
• Green

Question 10

What separates white light into the colors of the spectrum?

Answer 10

Refraction

Question 11

What type of cells in the retina detect certain wavelengths of light?

Answer 11

Cone cells

Question 12

What do we see when the brain responds to signals from cone cells?

Answer 12

Colors

Question 13

What is one way of producing color using a transparent object?

Answer 13

Filter

Question 14

What does a colored filter do?

Answer 14

Transmits some colors and allows others to pass through

Question 15

What is the color of the filter the same as?

Answer 15

The color of light it transmits

Question 16

What is a colored material that absorbs certain colors and reflects others called?

Answer 16

Pigment

Question 17

What happens when mixing pigments?

Answer 17

It actually changes the reflected color

Question 18

What is light in which the waves vibrate in only one direction called?

Answer 18

Polarized light

Polarized light is often used in sunglasses and photography to reduce glare.

Question 19

What is the term for light produced by heating a piece of metal until it glows?

Answer 19

Incandescent light

Incandescent light is common in traditional light bulbs.

Question 20

What type of light consists of only one wavelength that travels with its crests and troughs aligned?

Answer 20

Monochromatic light

Monochromatic light is used in lasers.

Question 21

What is the type of reflection in which light striking a surface between two materials reflects totally back into the first material?

Answer 21

Total internal reflection

Total internal reflection is the principle behind fiber optics.

Question 22

What is the term for a material that transmits some light and blocks some light?

Answer 22

Translucent material

Examples of translucent materials include frosted glass and some plastics.

Question 23

What technique produces a 3-D photographic image without a lens?

Answer 23

Stereoscopy

Stereoscopy uses two images viewed from slightly different angles to create depth.

Question 24

What is an image of a distant object produced by the refraction of light through air layers of different densities called?

Answer 24

Mirage

A mirage is commonly seen in deserts or on hot roads.

Question 25

What are the primary colors of light?

Answer 25

Red, blue, yellow ## Footnote These colors can be combined to produce other colors in additive color mixing.

Question 26

What type of light spreads out and may contain more than one wavelength?

Answer 26

White light ## Footnote White light is made up of all colors of the spectrum combined.

Question 27

What type of light is produced without excessive loss of thermal energy?

Answer 27

Efficient light ## Footnote Efficient lighting includes LED and fluorescent lights.

Question 28

What is the term for a material that transmits almost all light?

Answer 28

Transparent material ## Footnote Examples include clear glass and clean water.

Question 29

What is the term for a material that allows no light to pass through?

Answer 29

Opaque material ## Footnote Opaque materials include wood, metals, and thick plastics.

Question 30

What generates incandescent lights?

Answer 30

Heating a piece of metal until it glows

Question 31

What percentage of energy is lost as thermal energy in incandescent lights?

Answer 31

90%

Question 32

How are fluorescent lights generated?

Answer 32

Using phosphors to convert UV to visible light

Question 33

What do fluorescent lights convert?

Answer 33

Ultra violet radiation to visible light

Question 34

How much more efficient are fluorescent lights compared to incandescent lights?

Answer 34

Use 1/5 electricity to produce the same amount of light

Question 35

How do the lifespans of fluorescent lights compare to incandescent lights?

Answer 35

Fluorescent lights last much longer than incandescent

Question 36

What is a key characteristic of neon lights?

Answer 36

Vivid, glowing colors

Question 37

What type of lights are often used in street lighting?

Answer 37

Sodium-vapor lights ## Footnote Sodium-vapor lights are known for their efficiency and distinctive yellow hue.

Question 38

What is a characteristic of tungsten-halogen lights?

Answer 38

Create intensely bright light ## Footnote Tungsten-halogen lights have a filament that operates at a higher temperature, resulting in increased brightness.

Question 39

What happens to the filament in tungsten-halogen lights?

Answer 39

Becomes much hotter ## Footnote The increased temperature allows for more intense light output compared to standard incandescent bulbs.

Question 40

What defines the wavelength (color) of a laser?

Answer 40

Material used ## Footnote Different materials produce lasers of various colors based on their atomic structure.

Question 41

Do laser beams spread out?

Answer 41

No ## Footnote Laser beams remain narrow due to their coherent nature.

Question 42

What is meant by coherent waves?

Answer 42

Waves that combine to form a wave with a constant wavelength and frequency ## Footnote Coherence in laser light results in a highly focused and intense beam.

Question 43

List four uses of lasers.

Answer 43

* Shrink tumors * Destroy kidney stones * Repair retina * Improve vision ## Footnote Lasers are utilized in various medical applications due to their precision and effectiveness.