sound/light waves

Question 1

how does sound travel

Answer 1

sound vibrates a particle which then vibrates the nearest particle which then vibrates the next particle and so on until it reaches the ear

Question 2

explain how the speed of sound changes when it travels through solids, liquids and gases

Answer 2

sound travels fastest in solids, due to the particles being closer together, and slower in gases

Question 3

can sound travel through a vacuum

Answer 3

sound cannot travel through a vacuum because there are no particles

Question 4

can sound be reflected? what is this called

Answer 4

yes, its called an echo

Question 5

speed of light

Answer 5

300 million m/s

Question 6

speed of sound

Answer 6

340 m/s

Question 7

what is the relationship between the amplitude and the volume of the sound

Answer 7

as the volume increases, so does the amplitude

Question 8

what is the relationship between the frequency and the pitch of the sound

Answer 8

as the pitch of the sound increases, the frequency of the sound wave also increases

Question 9

give the auditory range of humans

Answer 9

20-20,000 Hz

Question 10

what are ultra sonic sounds

Answer 10

sounds above human range of hearing, above 20,000 Hz, so cannot be heard. used by animals to communicate

Question 11

explain how sounds are heard

Answer 11

a sound makes a vibration which passes through the air into the outer ear. this passes through the ear canal, the eardrum vibrates causing the ossicles to vibrate, the cochlea to vibrate which then sends a message to the brain via the auditory nerve

Question 12

what can loud sounds do to ears

Answer 12

cause temporary or even permanent hearing problems. e.g. tinnitus

Question 13

how do light waves travel

Answer 13

only straight lines, fastest thing known to man.

Question 14

when is light the fastest

Answer 14

in a vacuum

Question 15

what are luminous and non-luminous objects

Answer 15

luminous produce light, non-luminous reflect/absorb/transfer light

Question 16

state the law of reflection

Answer 16

angle of incidence is equal to the angle of reflection

Question 17

what is refraction

Answer 17

refraction is how light changes speed when it meets a boundary between to different medians

Question 18

what is white light and how can it be dispersed

Answer 18

white light is a mixture of all colours of light of differing frequencies. white light can be split into all the different colours of light by using a prism. red light has the longest wavelength, and violet the shortest