Physics

Question 1

waves

Answer 1

motion of disturbance

Question 2

mechanical eaves

Answer 2

include sound waves, require a medium

Question 3

non-mechanical

Answer 3

travel thru a vacuum, light waves etc

Question 4

pulse wave

Answer 4

singular traveling pulse

Question 5

periodic wave

Answer 5

repeatedly generated

Question 6

transverse

Answer 6

wave and particle motion perpendicular

Question 7

crest

Answer 7

highest point above eq

Question 8

trough

Answer 8

lowest point below eq

Question 9

amplitude

Answer 9

max distance from eq (measured from eq to c or t)

Question 10

longitudinal

Answer 10

wave and particle motion parallel like sound waves

Question 11

how do waves transfer energy

Answer 11

Waves transfer energy by the vibration of
matter The energy moves while the particles
vibrate locally and the medium remains in
place.

Question 12

rate of energy transfer

Answer 12

The rate of energy transfer depends on the
amplitude. The greater the amplitude the
more energy the wave carries in a given time
interval.

Question 13

Wavelength

Answer 13

distance wave travels for one cycle

measure from cr to cr or tr to tr

Question 14

high density/pressure

Answer 14

crest

Question 15

low density/pressure

Answer 15

trough

Question 16

period and frequency

Answer 16

The source of wave motion is a vibrating object
Period is the time it takes for one full wavelength to pass any given point
Frq is the number of wavelengths that pass a given point in second

Question 17

speed

Answer 17

wavelength/time

Question 18

Wave interference

Answer 18

is the phenomenon that occurs when two waves meet while traveling along the same medium.

Question 19

Constructive interference

Answer 19

is a type of interference that occurs at any location along the medium where the two interfering waves have a displacement in the same direction.

Question 20

Destructive interference

Answer 20

is a type of interference that occurs at any location along the medium where the two interfering waves have a displacement in the opposite direction (noise cancellation)

Question 21

Reflection at a Boundary: (free end)

Answer 21

Now consider what would happen if the end of the rope were free to move. Instead of being securely attached to a lab pole, suppose it is attached to a ring that is loosely fit around the pole. Because the right end of the rope is no longer secured to the pole, the last particle of the rope will be able to move when a disturbance reaches it. This end of the rope is referred to as a free end.

Question 22

Reflection at a Boundary: (fixed end)

Answer 22

First consider an elastic rope stretched from end to end. One end will be securely attached to a pole on a lab bench while the other end will be held in the hand in order to introduce pulses into the medium. Because the right end of the rope is attached to a pole (which is attached to a lab bench) (which is attached to the floor that is attached to the building that is attached to the Earth), the last particle of the rope will be unable to move when a disturbance reaches it. This end of the rope is referred to as a fixed end.

Question 23

resonance

Answer 23

forced vibrations at the same
fr cause an increase in
amplitude

Question 24

standing waves

Answer 24

a vibration of a system in which some particular points remain fixed while others between them vibrate with the maximum amplitude.
causes:
· Reflections at Two Boundaries (at either end)
· Constructive/Destructive Interference

Question 25

nodes

Answer 25

``` complete destructive interference (ends of strings can't vibrate) ```

Question 26

antinodes

Answer 26

increased amplitude midway between adjacent nodes

Question 27

distance btwn nodes

Answer 27

half wavelength

Question 28

fundamental frequency

Answer 28

lowest frequency of standing wave

Question 29

Harmonics

Answer 29

: integral multiples of the fundamental | frequency.

Question 30

n

Answer 30

n is called the harmonic number and | is equal to 1, 2, 3 ...

Question 31

closed both ends

Answer 31

v/2L

Question 32

open both ends

Answer 32

nv/2l

Question 33

open one end closed other

Answer 33

nv/4l ONLY ODD HARMONIC

Question 34

Timbre

Answer 34

- sound quality due to the mixture of harmonics at varying intensities The first harmonic (fundamental frequency) determines overall pitch; other harmonics change timbre (overtones)

Question 35

beats

Answer 35

interference of waves of slightly different frequencies that result in a sound that alternates between being loud and soft

Question 36

Number of Beats per Second =

Answer 36

Difference btwn the 2 Frequencies

Question 37

order of waves

Answer 37

radio, micro,

Question 38

order of light waves

Answer 38

radio, micro, infra, ultraviolet, x rays, gamma | frq increases, wl decreases

Question 39

visible light

Answer 39

btwn infra and UV

Question 40

what are microwaves used for

Answer 40

radar, atomic/molecular research, aircraft nav, microwave ovens

Question 41

infrared

Answer 41

thermal imaging, photography, pt

Question 42

gamma rays

Answer 42

exam thick material, radiation therapy treatment, food irradiation

Question 43

intensity

Answer 43

light bulbs are rated by light input and light output

Question 44

luminous flux

Answer 44

rate at which light emitted from source

Question 45

illuminance

Answer 45

luminous flux/area, decreases as u move from light source | light intensity

Question 46

pitch

Answer 46

perceived highness or lowness of sound

Question 47

variables affecting speed of sound

Answer 47

closeness of particles (solid, liquid, gas) | temp of particles (increase in t = increase in v)

Question 48

types of sound waves

Answer 48

infrasonic - under 20 Hz audible (humans) btwen 20 and 20k ultrasonic over 20k

Question 49

doppler effect

Answer 49

increase or decrease in frequency due to source moving | causes change in pitch

Question 50

sound intensity

Answer 50

amount of energy flowing per unit perpendicular to the direction in which the sound waves are travelling. power/area