YR2_T1_LSN7

• Science
• Middelbare school
• havo, vwo
• Leerjaar 2

YR2_T1_LSN7

Topic 1.5

Plan for today

• Homework check (T1.3)
• Explanation T1.5  

Homework check:

• Open the answers of T1.3 on Classroom
• Correct your hw in a different colour.
• Bring up your textbook and notebook when your name is called. 

Topic 1.5 - Learning Goals:

I can...

• Read a sound wave diagram and determine wavelength and amplitude
• Calculate the frequency of a sound based on the wavelength
• Label the parts of the ear and explain their function
• Explain how the brain receives information about the different sound frequencies
• Explain how hearing loss can occur as a result of exposure to loud sounds

Topic 1.5 - Key Words:

• Semicircular canals
• Ossicles
• Pitch
• Auditory nerve 
• Auricle
• volume  

• Cochlea
• Amplitude 
• Decibels
• Eustachian tube
• Frequency
• Hertz (Hz)

1.5 - Sound waves

Sound is a form of energy that travels in waves

• It can only travel when there are molecules to pass on the sound wave
• Waves are identified by pitch and by volume

The pitch is measured by the number of waves per second in Hertz (Hz)

The volume is measured by the amplitude of the sound wave in decibels (dB) 

1.5 - Sound waves

1.5 - Frequency

Frequency is the number of wavelengths per second (Hz) 

Wavelength: the time of one wavelength is expressed in seconds(s)

Formula: 

What is the frequency
if one wavelenght is one millisecond?

1. 10Hz
2. 1000Hz
3. 100Hz
4. 1Hz

1.5 Ears are the detectors of sound

1.5 - Ears are the detectors of sound:

• Vibrations in the air cause the eardrum to vibrate.
• This passes on the vibrations to the ossicles.
• The ossicles vibrate the cochlea.
• This transfers the signals to the auditory nerve.

1.5 The cochlea detects different frequencies

1.5 Hearing age test

Click the link

1.5 - Ultrasound:

• Humans can not hear very high pitched sounds 
• These are called ultrasound

Doctors use ultrasound to check on the health of a baby in the womb

1.5 - Sound can be used to locate objects

• Bats use sound to locate their prey
• Fishing boats use ultrasound to find a school of fish

Hw for next time:

Theory lesson:

• Complete the exercises of Topic 1.5 (p.42-46).
• Study the glossary of Topics 1.5 on StudyGo.