# 1 CWC Prentice Hall Physical Science Chapters 21, 23, 24, and 25 Flashcards

## 56 terms · I used these flashcards on my semester exams. They are just vocab for chapters 21, 23, 24, and 25

### electromagnetism

relationship between electricity and magnetism

### solenoid

long coil of wire that acts like a magnet when current flows through it

### electromagnet

solenoid with a magnetic material such as iron inside its coils

### electric motor

device that uses an electromagnet to convert electrical energy to mechanical energy that is used to do work

### galvanometer

device that uses an electromagnet to detect small amounts of current

### induced current

current produced in a wire exposed to a changing magnetic field

### electromagnetic induction

process by which a current is produced by a changing magnetic field

### generator

device that uses electromagnets to convert mechanical energy to electrical energy

### transformer

device that increases or decreases the voltage of alternating current

### waves

traveling disturbance that carries energy from one place to another

### vibration

movement that follows the same path over and over again

### medium

material through which a mechanical wave travels

### mechanical waves

wave that disturbs a medium

### crests

highest points on a wave

### troughs

lowest points on a wave

### amplitude

greatest distance from crest of a wave

### wavelength

distance between two consecutive similar points on a wave

### frequency

number of waves that pass a certain point in a given point in time

### transverse waves

wave in which the motion of the medium is at right angles to the direction of the wave

### longitudinal waves

wave in which the motion of the medium is parallel to the direction of the wave

### surface wave

wave that consists of a combination of transverse and longitudinal waves and occurs at the surface between two different mediums

### formula for speed

speed= Frequency x Wavelength

### reflection

bouncing back of waves upon reaching another surface

### law of reflection

States that the angle of incidence (i) is equal to the angle of reflection (r)

### refraction

bending of waves due to a change in speed

### diffraction

the bending of waves around the edge of an obstacle

### interference

interaction of waves that occur at the same place at the same time

### standing wave

wave that does not appear to be moving; occurs at the natural frequency of the material

### resonant frequency

frequency at which a standing wave occurs

### pitch

property of sound that depends on frequency

### ultrasonic

sounds waves with frequencies higher than 20000 Hz

### infrasonic

sound waves with frequencies lower than 20 Hz

### Doppler effect

change in sound or light that occurs whenever there is motion between the source and its observer

### intensity

the amount of energy carried by a wave in a certain amount of time; determines the loudness of a sound

### acoustics

science of sound and its interactions

### sound quality

blending of pitches to produce sound; timbre

### fundamental tone

note produced at its lowest frequency at which a standing wave occurs

### overtones

tone produced at frequencies higher than the fundamental at which a standing wave occurs

### Sonar

High-frequency ultrasonic waves are used in this system

### outer ear

part of the human ear that funnels sound waves into the ear

### eardrum

stretched membrane in the ear that vibrates at the same frequency as the sound waves that enter the ear

### middle ear

part of the ear that receives vibrations from the eardrum and contains the hammer, anvil, and stirrup

### inner ear

liquid-filled portion of the ear; receives vibrations from the middle ear

### cochlea

port of the ear that contains hundreds of nerve cells attached to nerve fibers

### electromagnetic spectrum

arrangement of electromagnetic waves in order of wavelength and frequency

electromagnetic waves with the longest wavelengthes and lowest frequencies in the electromagnetic spectrum

### modulation

variation; in the particular, in the amplitude or frequincy of an electromagnetic wave

### microwaves

high-frequency radio wave used primarily for communication

use of short-wavelength microwaves to locate objects and monitor speed

### luminous object

object that is capable of giving off its own light

### illuminated object

object that reflects light and does not produce its own light

### incandescent light

light produced by heat

### fluorescent light

light produced by bombarding molecules of gas in a tube

### Neon light

cool light produced when elecctrons fflow through a glass tube filled with gas

### photon

tiny bundle of light energy

### photoelectric effect

process by which light can be used to knock electrons out of a metals; can only be explained using the particle nature of light