YR2_T1_LSN14

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

Get ready:

Macbook:

• Google Classroom
• Lessonup
• Kwizl

Textbook & Notebook closed.

YR2_T1_LSN14

Topic 1.5

Homework check:

• Open the docs 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 - Soundwaves:

If a sound gets louder, what changes?

1. frequency
2. wavelength
3. amplitude

If a sound gets higher in pitch, what changes?

1. frequency
2. wavelength
3. amplitude

1.5 - Frequency:

• Frequency is the number of wavelengths per second (Hz) 
• Wavelength: the time of one wavelength is expressed in seconds(s) 

• Formula:  

If one cycle(wavelength) is 1 millisecond, what is the frequency?

If one cycle(wavelength) is 500 milliseconds?

If the frequency is 250 Hz, what is the time of one cycle?

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 - 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