Waves - Sp4

Question 1

what angle are the vibrations to a transverse wave

Answer 1

90 degrees - perpendicular

Question 2

What types of transverse waves are there

Answer 2

electromagnetic, S-waves, waves in water

(MOST WAVES ARE TRANSVERSE)

Question 3

Using a spring as an analogy, how are transverse waves created

Answer 3

The spring moves up and down to create the pattern more commonly seen

Question 4

At which angle do vibrations within longitudinal waves occur?

Answer 4

they travel along the same plane as the wave at the same angle (parallel)

Question 5

What types of waves are longitudinal?

Answer 5

P-waves and sound waves

Question 6

What do you call the compressed parts of longitudinal waves

Answer 6

compressions

Question 7

what do you call the extended parts within longitudinal waves

Answer 7

rarefractions

Question 8

which 2 equations calculate wave speed?

Answer 8

Frequency x wavelength

or

distance/time

Question 9

what are the purposes of waves?

Answer 9

to transfer energy + information (not matter) in direction they are travelling

Question 10

How do waves work?

Answer 10

The particles in a medium vibrate to transfer energy between eachother

Question 11

what is the definition of frequency

Answer 11

number of complete cycles of the wave passing through the same point (eg crest to crest) per second

Question 12

how is frequency measured?

Answer 12

in Hz (1Hz = 1 wave a second)

Question 13

What is a period?

Answer 13

number of seconds taken for a full cycle of the wave to occur

Question 14

what is the difference between transverse and longitudinal waves?

Answer 14

transverse = perpendicular (all electromagnetic + s waves)
longitudinal waves = parallel (sound + p waves)

Question 15

how does one measure velocity of sound in air?

Answer 15

speed = frequency x wavelength

Question 16

how does one measure velocity of sound on the surface of the water?

Answer 16

speed = frequency x wave length

Question 17

How does the direction of a wave change through different materials? and why does it? when does the direction not change?

Answer 17

due to different densities, the speed changes when a wave crosses a boundary meaning change in speed can cause a change in direction (if it hits it at an angle (this is refraction)) - if travelling along the normal the direction does not change.

Question 18

What happens to the direction of a wave when the change in speed is greater

Answer 18

the wave will bend more

Question 19

what is the effect of a wave being reflected?

Answer 19

reflected light is scattered in all directions, creating distorted images

Question 20

what are the effects of waves being refracted

Answer 20

change direction and speed

Question 21

effects of waves being absorbed and transmitted?

Answer 21

energy is transferred to the particles in the object - causing vibrations

Question 22

Describe how changes in velocity, frequency and wavelength are related when sound waves go from one medium to another

Answer 22

the velocity is directly proportional to the wavelength - any change in wave length is changed in velocity (e.g when the wave gets longer, the velocity increases). frequency doesn’t change.

Question 23

list the parts of the human ear in order of how they transmit vibrations

Answer 23

soundwaves reach ear drums - cause them to vibrate

passes on to ossicles

then through semi-circular to the cochlea

turned vibrations into electrical signals sent to your brain

Question 24

what is the function of the ear drum

Answer 24

to create vibrations

Question 25

function of the cochlea

Answer 25

turn vibrations into electrical signals

Question 26

how are sound waves in air converted into vibrations in solids

Answer 26

as the wave travels through air, it compresses and refracts - upon hitting a solid object, the air particles hitting cause the particles in the solid to move back and forth - these then hit the particles next in line and so on

Question 27

what factors effect how well sound waves transfer energy to solids

Answer 27

distance to object, speed of wave, the amount of particles to move in the area

Question 28

why can the human ear only detect a range of freqencies

Answer 28

due to shape and size - as it is small, the ear can only transfer a certain amount of energy without being hurt