Light Quiz
Questions: 16 · 10 minutes
1. A clear plastic sheet, wax paper, and cardboard are placed one at a time over a flashlight. Which material should produce the darkest shadow because it transmits the least light?
The clear plastic sheet
The cardboard
All three should transmit equal amounts
The wax paper
2. Light passes through frosted glass, but objects seen through it look blurred because the light is scattered. How is the glass best classified?
Transparent
Translucent
Opaque
Reflective
3. A green sheet of paper is viewed in a room illuminated only by red light. How will the paper most likely appear?
Very dark or nearly black
Bright green
White
Bright blue
4. Visible light lies between which two regions of the electromagnetic spectrum?
Ultraviolet and X-rays
Microwaves and infrared
Infrared and ultraviolet
Radio waves and microwaves
5. A beam of light travels from air into glass. Which property of the light remains unchanged at the boundary?
Its speed
Its direction in every case
Its wavelength
Its frequency
6. A pencil partly submerged in water appears bent at the water's surface. Which behavior of light causes this effect?
Diffraction around the pencil
Polarization by the pencil
Reflection only from the water's surface
Refraction as light passes between water and air
7. When white light passes through a typical glass prism, which visible color is generally refracted the most?
Red
Yellow
Violet
Green
8. A convex lens forms a sharp image of a distant tree on a screen. How should that image be described?
Virtual and upright
Real and inverted
Virtual and inverted
Real and always upright
9. Approximately how fast does light travel through a vacuum?
300 meters per second
300,000 meters per second
30,000 kilometers per second
300,000 kilometers per second
10. On a screen using additive light mixing, what color is produced when red light and green light overlap at similar intensities?
Cyan
Blue
Yellow
Black
11. Why does a simple pinhole camera form an upside-down image?
The pinhole reflects the image from its inner surface
Light travels in straight lines, so rays from opposite parts of the scene cross at the pinhole
The screen rotates the incoming light by 180°
The pinhole separates white light into different colors
12. A light ray strikes a flat mirror at an angle of 35° measured from the normal. What is its angle of reflection, also measured from the normal?
35°
55°
70°
17.5°
13. During a lunar eclipse, why does the Moon become darkened?
The Moon moves between Earth and the Sun
Clouds in Earth's atmosphere block our view of the Moon
Earth moves between the Sun and the Moon, placing the Moon in Earth's shadow
The Sun temporarily stops emitting visible light toward the Moon
14. How does an image in an ordinary flat plane mirror compare with the object?
It is upright, virtual, and the same size
It is upright and always larger
It is real and can be projected onto a screen
It is inverted top to bottom and smaller
15. A small object sits between a point-like flashlight and a wall. If the object moves closer to the flashlight while the wall stays fixed, what generally happens to its shadow on the wall?
It becomes larger
It stays the same size but becomes brighter
It becomes smaller because less light reaches the object
It disappears completely
16. Which sequence of light behaviors is chiefly responsible for a primary rainbow forming in raindrops?
Only reflection from the outer surfaces of droplets
Diffraction followed by polarization
Absorption of all colors except one
Refraction and dispersion, internal reflection, then further refraction