10.3 Hearing + 10.7 Brain

Question 1

What is sound produced by

Answer 1

Vibrations of objects

Question 2

Whats frequency
Unit

Answer 2

Vibrations made per second
Hertz

Question 3

Relationship between tuning fork length and frequency

Answer 3

Shorter prong higher frequency
越短越快越高音

Question 4

how is sound transmitted

Answer 4

1. Object vibrates
2. Push on surrounding air particles
3. Particles vibrate, travel through air

Question 5

Sound must travel through a ____, it can be a _____, ______, _____

Answer 5

Medium
Solid liquid gas

Question 6

Sound is transmitted through __________ in these medias

Answer 6

Vibrations of particles

Question 7

Why can’t sound travel through vacuum

Answer 7

No air, no particles transmit sound, no sound can be heard

Question 8

Speed of sound in diff media

Answer 8

Fastest in solids
Slowest in gases

Question 9

Why cant sound be heard in space

Answer 9

Space is a vacuum, sound cant travel through it

Question 10

Ear structure

Answer 10

Pinna, ear canal, ear drum, ear bones, cochlea, auditory nerve

Question 11

How we hear

Answer 11

1. Pinna collects sound, directs into ear canal
2. Travels down ear canal to middle ear
3. sound causes eardrum vibrate, vibrations transmitted to ear bones
4. 3 ear bones amplify eardrum’s vibrations, transmit to inner ear
5. Sensory hair cells in cochlea detect vibrations, produce signals
6. Signals fr sensory hair cells sent to brain through auditory nerve , interprets signals as sounds

Question 12

Why cant hear clearly
What helps them hear better

Answer 12

Ear bones / sensory hair cells in cochlea not function properly
hearing aid / cochlea implant

Question 13

Limitation

Answer 13

Audible frequency range; only hear within certain range of frequency, 20-20000 Hz

Question 14

Whats noise, sources, cause

Answer 14

Unwanted, disturbing
Traffic, construction work, Humm a voices, loud music
Noise pollution

Question 15

Measure sound level
Unit

Answer 15

Decimal meter
dB

Question 16

Effects of noise depends on
Cause
Daily life problems

Answer 16

Sound level, duration of exposure
Extremely high sound levels / prolonged exposure to loud sound
Tinnitus, hearing loss
Disturb study work sleep, mental stress

Question 17

Protect hearing

Answer 17

Low volume
Shorten time, noisy environment
Ear plugs, protectors
X. Pick w hard obj

Question 18

Sense organs ___________ and _________ to brain to produce ________. Brain uses signals from sense organs to help us _________.

Answer 18

Detect stimuli
Sends signals
Senses
Respond to stimuli

Question 19

Role of brain

Answer 19

Sense organs cant produce senses, they’re detect stimuli and sends signals to brain.
Brains acts as coordinator

Question 20

How brain makes response

Answer 20

1. Integrates and interprets signals
2. Produce sense
3. Decide action
4. Signal muscle through nerves
5. Make response

Question 21

Whats reaction time

Answer 21

Time between detecting a stimulus and making response

Question 22

How many nerve cells does brain hv
How signals sent fr cell to cell

Answer 22

10B +
Long extensions

Question 23

Parts of brain, functions

Answer 23

Cerebrum:
1. Inter grants, interprets signals
2. Signals muscle to make response
3. Intelligence, memory, thinking

Cerebellum:
1. Coordinates muscles, movements
2. Maintain body balance

Medulla:
1. Basic life functions, heartbeat, breathing, blood pressure

Question 24

What causes illusions

Answer 24

Brain interprets signals incorrectly