Chapter 14- Nature Of Waves

Question 1

Mechanical

Answer 1

Need a medium for transmission
Generated by vibrating sources

Energy from the vibrations is transferred to the medium and is transmitted by the particles within it

Question 2

Longitudinal

Answer 2

Oscillations parallel to direction of energy transfer

Question 3

Transverse

Answer 3

Oscillations of particles perpendicular to direction of energy transfer

Question 4

Longitudinal vocab of movement

Answer 4

Compressions and rarefractions

Question 5

Examples of transverse waves

Answer 5

Water waves

Question 6

Example if longitudinal

Answer 6

Sound waves

Question 7

Amplitude def

Answer 7

Maximum displacement from the mean position

Metres, m

Question 8

Period def

Answer 8

Time taken for one complete oscillation

Seconds, s

Question 9

Frequency def

Answer 9

Number of complete oscillations per second

Hertz, Hz

Question 10

Frequency eq

Answer 10

f= 1/T

Question 11

Type of graph for oscillating particles

Answer 11

Displacement- time graphs

Question 12

Method of creating an oscillation drawing

Answer 12

Pen attached to spring with a mass

Move a piece of white card at constant point

Or
Use motion sensor (transmitter on spring and a receiver)

Question 13

Phase def

Answer 13

The phase of an oscillation refers to the position within a cycle that the particle occupies in relation to the cycle or other particle

Question 14

Antiphase

Answer 14

Two oscillations are half a cycle out of step with eachother

Question 15

Phase difference

Answer 15

The calculated space between two oscillations

Question 16

360*= (radians)

Answer 16

2 pie

Question 17

180*

Answer 17

1 pie

Question 18

90*

Answer 18

Pie/2

Question 19

270*

Answer 19

3/2 pie

Question 20

What dies displacement-distance graph show

Answer 20

Shows the phase relationship of masses

Question 21

Wave profile def

Answer 21

Cross section of the wave at a particular point

Question 22

Difference between displacement-time and displacement-distance graphs

Answer 22

1) represents the position of all the particles along the sections of the wave as opposed to
2) showing the motion of a single particle within the wave

Question 23

Degrees to radians calc

Answer 23

Pie/180 x angle in degrees

Question 24

Radians to degrees calc

Answer 24

180/pie x angle in radians

Question 25

Wavelength def

Answer 25

Distance between two adjacent points in phase

Question 26

Electromagnetic waves are created

Answer 26

When charged particles are accelerated

Question 27

What continuously varies in an electromagnetic wave

Answer 27

Electric and magnetic fields Have sand frequency as the oscillator

Question 28

Magnetic field for electromagnetic wave

Answer 28

Is in the vertical At right angles to the electric field oscillation

Question 29

Electric field oscillation for electromagnetic wave

Answer 29

In the horizontal Right angles to the magnetic field oscillation

Question 30

Electric or magnetic fields do not require

Answer 30

A material medium

Question 31

Electrical or magnetic fields cannot exist without

Answer 31

Eachother

Question 32

Anagram for electromagnetic field

Answer 32

``` Red (radio) Mints (microwave) In (infrared) Violet (visible light) Underpants (ultraviolet) X-ray Grapes (gamma) ```

Question 33

Radio or gamma? | Shortest wavelength

Answer 33

Gamma

Question 34

Gamma ray uses

Answer 34

In medicine to destroy tumours To sterilise instruments (Highly penetrating rays)

Question 35

X-ray uses

Answer 35

More controllable than gamma Used in medicine for diagnosis and treatment Can detect faults in materials and metals and crystals

Question 36

Ultraviolet uses

Answer 36

Stimulates vitamin D in skin creating tan Makes materials fluorescent Used in lamps etc

Question 37

Visible light uses

Answer 37

Focused on eye retina creates image in brain Photographic film Energy source for plant photosynthesis

Question 38

Infrared uses

Answer 38

Radiated by warm bodies Used for heating and cooking Also in thermal imaging devices

Question 39

Microwave uses

Answer 39

Energy transferred to water molecules in food by resonance of microwave frequencies Used in mobile phones and satellite communications

Question 40

Radio uses

Answer 40

Wide range of frequencies allow many signals to be transmitted Telescopes can detect faint sources in space

Question 41

Speed of travelling wave depends on (2)

Answer 41

- nature of wave | - medium it is travelling through

Question 42

Wave speed equation

Answer 42

Speed = wavelength / time period (to complete one cycle)

Question 43

Wave equation

Answer 43

Wave speed = frequency x wavelength