22 terms

Physical Science Module 15

Electromagnetic Wave
A transverse wave composed of an oscillating electric field and a magnetic field that oscillates perpendicular to the electric field.
The law of reflection
The angle of reflection equals the angle of incidence.
Explain the wave theory of light, the particle theory of light, and the quantum-mechanical theory of light.
Wave theory: light is two transverse waves, one made of an oscillating magnetic field, and the other made of an oscillating electric field.
Particle theory: light is a beam of individual particles called photons.
Quantum-mechanical theory: light is both a particle and a wave. it is made up of individual packets that behave like particles, but the packet is actually made up of a wave.
Sound waves cause air to oscillate. What do light waves oscillate.
Electric and magnetic fields.
What does Eintstein's Special Theory of Relativity say about the speed of light?
Nothing with mass can travel faster than the speed of light.
Light is traveling through water and suddenly breaks the surface and travels through air. Did light's speed increase, decrease, or stay the same once it left the water?
Order the following colors in terms of increasing wavelength: orange, violet, yellow, green. In other words, list the color corresponding to the smallest wavelength first, end with the color that corresponds to the longest wavelength.
Violet, green, yellow, orange.
Order the colors in problem #6 in terms of increasing frequency. Once again, start with the lowest frequency and end with the highest frequency.
orange, yellow, green, violet.
Do radio waves have higher or lower frequencies than visible light? What about X-rays?
Lower. Higher.
Infrared light is given off by any object that is losing heat. The human body is almost always losing heat to the environment, Why, then, don't human bodies glow at night, since they are emitting light?
It isn't visible light.
Light hits a mirror, making an angle of 15 degrees relative to a line drawn perpendicular to the mirror's surface. What angle does the reflected light make with the same line?
The reflected light also makes a 15 degree angle relative to that line.
In the following diagram, will the man see his foot, despite the fact that the mirror does not reach the ground?
When light travels from one substance to another, what two things can happen to the direction of the light ray's travel?
The light ray can be reflected or refracted.
In a physics experiment, a light ray is examined as it travels from air into glass. If the angle that the light ray makes with a line perpendicular to the glass surface is measured will the refracted ray bend toward or away from that line.
The light will bend towards the perpendicular line.
When you look at objects underwater from above the water, they appear to be at a different position than their actual position. Why?
When light travels from water to air, it bends. This causes your mind to form a false image of the object in a slightly different location.
In order for you to see a rainbow, what three conditions must be met?
There must be water droplets in the air, the sun must be shining from behind you, and the sun must be at a certain angle/height.
What is the difference between a converging lens and a diverging lens?
A converging lens causes the light waves to bend inward, whereas diverging lenses cause the light rays to bend outward.
Which of the following lenses is a converging lens? Which is a diverging lens?
a. b.
What is special about the way the eye focuses light as compared to the way a camera focuses light?
The eye's lens actually changes shape, whereas the camera just adjusts the lens's position.
Suppose the cone cells on your retina that sense red light no longer work. If you look at a white piece of paper, what color would it appear to be? if you look at a red piece of paper, what color would it appear to be?
The white paper would appear to be blue-green or cyan. The red paper would appear to be black.
A shirt is dyed so that it looks violet. What colors of light does the dye absorb?
Red, yellow, orange, green, blue, and indigo.
A cyan dye is made of a mixture of substances that absorb all light except blue and green. If you took a cyan piece of paper and placed it in a dark room and shined a red light on it, what would you see? What would you see if you shined a green light on it?
In the red light, then, the paper would look black. In the green light, the paper would look green.