Science Quiz: Waves Section 1

Speed of light

300,000 km/s in empty space. 197,000 km/s in glass. Travels 150,000,000 km to Earth. Eight and a half minutes.

Refraction

A change in wave direction that occurs when a wave passes from one material to another and changes speed.

Wave

A disturbance that moves through matter or space.

Crest

A high point in a transverse wave.

Explain how amplitude, energy, sound and intensity are related.

Amplitude is how much energy a sound wave has, energy is contributed to the sound and how loud it will be, the louder the noise, the higher the intensity.

Amplitude

Depends on the energy carried by a wave.

Wave Speed

Equals the wavelength times the frequency.

Intensity of light waves

Intensity determines the brightness of light.

Explain why sound travels faster through iron than through air.

Iron is a physical object, a solid. Sound energy is more productive with more matter, thus iron will be better than air, because air doesn't have as much matter or objects to bounce off of.

Parts of the eye and how we see.

Lens, pupil, cornea, retina, focal point, and optic nerve. Light passes through the cornea and into the lens, from there, the lens changes shape to focus on the object that is near or far, the info is then sent to the retina.

Light waves

Light waves are electromagnetic waves. This means that light waves can travel through both matter and empty space. Light travels fastest through empty space because there are no particles.

The _________ of the particles hardly _________ at all.

Locations, changes.

Trough

Low point in a transverse wave.

In water waves, energy is transferred by collisions between water _________.

Molecules.

Transverse Wave

Move particles of matter at right angles (up and down).

Compressional Wave

Move particles of matter in the same direction as wave.

Waves are usually produced by something _________ back and forth or __________.

Moving, vibrating.

Does sound travel outside Earth's atmosphere?

No, because sound waves, (mechanical waves), only travel through matter, and not empty space.

The ________ of waves depend on the _______ that produce them.

Properties, vibrations.

Compression

Region where coils are closest together for a compressional wave on a spring coil.

Rarefaction

Region where coils are farthest apart for a compressional wave on a spring coil.

Reverberation

Repeated echoes.

Rod and cone cells.

Rod cells are sensitive to dim light. Cone cells enable you to see colors.

Middle Ear

Sound amplifier. It consists of the ear drum, and three tiny bones called the hammer, the anvil, and the stirrup. The ear drum vibrates, this sound travels to the three bones, and the sound is amplified.

Outer Ear

Sound collector. It consists of the part you can see and the ear canal. The visible part looks like a funnel and it helps the ear collect sound and send it to the ear canal.

Inner Ear

Sound sender/transmitter. It contains the cochlea, which is filled with fluid and has tiny hair-like cells. Vibrations are transmitted to the hair cells. The movements of the hair cells produce signals that travel to your brain, where they are interpreted as sound.

Sound Waves

Sound waves are compressional waves.

Intensity

The amount of energy that a wave carries past a certain area each second. Measured in units of decibel (dB).

Loudness

The amount of noise something has. If a person claps there hands softly, than the loudness will be low. If the person clapped there hands hard, than the loudness will be high.

Law of Reflection

The angle to which the incoming wave makes with the normal equals the angle that the outgoing wave makes with the normal.

Diffraction

The bending of waves around an object.

Electromagnetic Spectrum

The complete range of electromagnetic wave frequencies and wavelengths. Low energy, low frequency, long wavelength. High frequency, short wavelength, and high energy. Radio waves, microwaves, infrared waves, visible light, ultraviolet waves, X-rays, gamma rays. Radio waves and microwaves have very low frequencies. Infrared, visible light, and ultraviolet waves have modest frequencies. X-rays and gamma rays have very high frequencies.

Wavelength

The distance between two crests/troughs, or two compressions/rarefactions.

How does a sound wave travel from a vibrating object through air?

The energy of an object, in this case a drum, carried by a sound wave is transferred by the collisions between the particles in the material the wave is traveling in.

Pitch

The human perception of the frequency of sound. High pitch=high frequency.

Frequency

The number of wavelengths that pass a point in a given time interval, measured in units of Hertz, which is the same as 1/s.

Echolocation

The process of locating objects by bouncing sounds off them.

Parts of electromagnetic waves.

Transverse waves, one up and down, one side to side. Contains an electric and magnetic part. Number of vibrations from electric and magnetic is frequency.

Mechanical Wave

Type of wave that can travel only through matter, including seismic waves.

Electromagnetic Wave

Type of wave that can travel through matter and empty space.

Wavelength and frequency of light

Wavelength (nm): one nanometer is equal to one billionth of a meter. 500 nm is 500 billionths of a meter, which is 600 trillion Hz.

Reflection

When a wave bounces off of an object.

Why do objects have color?

When light waves strike and object, some of them are reflected. The wavelengths of these determine the objects color.