Khan Academy Static

4D:Some sounds are loud (high amplitude) like someone yelling, while others are soft (low amplitude) like a whisper. Some sounds are low pitched (low frequency) like a fog-horn, while others are high-pitched (high frequency) like a pager. You may have even noticed that the pitch of an ambulance rises as it rushes towards you and drops as it moves away. This is the Doppler effect in action. Here you will learn about the basics of sound properties such as wavelength, frequency, and amplitude.

15255_Doppler_effect_formula_for_observed_frequency.html

15245_Production_of_sound.html

15252_Standing_waves_in_closed_tubes.html

15253_Standing_waves_in_open_tubes.html

15251_Ultrasound_medical_imaging.html

15254_Doppler_effect_introduction.html

15259_Doppler_effect_reflection_off_a_moving_object.html

15250_Why_do_sounds_get_softer_.html

15258_Doppler_effect_for_a_moving_observer.html

15247_Speed_of_Sound.html

15256_Doppler_effect_formula_when_source_is_moving_away.html

15248_Relative_speed_of_sound_in_solids_liquids_and_gases.html

15249_Decibel_Scale.html

15246_Sound_Properties_Amplitude_Period_Frequency_Wavelength_.html

15257_When_the_source_and_the_wave_move_at_the_same_velocity.html