Beath High School - Int 1 Physics1 Intermediate 1 Physics Sound and Music Sound Waves Speed of Sound Using Sound Amplified Sound

Beath High School - Int 1 Physics2 Intermediate 1 Physics Sound and Music Sound Waves

Beath High School - Int 1 Physics 3 Sound Waves Vibrations Musical instruments produce sound when part of the instrument v _ _ _ _ _ _ _ A guitar string vibrates when it is plucked. vibrates.

Beath High School - Int 1 Physics 4 Vibrations A trumpet blasts out sound when the a _ _ inside it vibrates Energy is transferred from the vibrating object to the listener by sound w _ _ _ _ which travel through the air. These sound waves make the air v _ _ _ _ _ _. air waves vibrate.

Beath High School - Int 1 Physics 5 Frequency Each note or sound has a frequency which is measured in h _ _ _ _ (Hz). A tuning f _ _ _ has the frequency engraved on it. This vibrating fork will produce 256 vibrations every s _ _ _ _ _. This means that 256 sound w _ _ _ _ are produced in one second. hertz fork second. waves

Beath High School - Int 1 Physics 6 Frequency F _ _ _ _ _ _ _ _ = number of waves produced in one second. Frequency

Beath High School - Int 1 Physics 7 Frequency A whistle produces a h _ _ _ _ _ frequency sound than a vibrating drum. The whistle has a much higher p _ _ _ _. higher The higher the pitch means the higher the f _ _ _ _ _ _ _ _ pitch frequency

Beath High School - Int 1 Physics 8 Detecting Sound S _ _ _ _ can be taken in by a microphone and a trace displayed on an oscilloscope. Sound

Beath High School - Int 1 Physics 9 Loud and quiet A loud sound transfers more e _ _ _ _ _ so the oscilloscope trace will have a l _ _ _ _ amplitude. The amplitude of a wave is the distance from the m _ _ _ _ _ of the wave to the top or bottom of the wave. energy large middle

Beath High School - Int 1 Physics 10 Loud and quiet

Beath High School - Int 1 Physics 11 A soft/quiet sound transfers l _ _ _ energy so the oscilloscope trace will have a s _ _ _ _ amplitude Loud and quiet less small

Beath High School - Int 1 Physics 12 The effect of changing the frequency of a note can be seen on the oscilloscope screen. High and Low Frequency Sound _ has a higher frequency than sound _. B A

Beath High School - Int 1 Physics 13 frequency: (Hz) one octave t _ _ octaves If the frequency is doubled, we say that sound B is an o _ _ _ _ _ higher than sound A. High and Low Frequency octave two

Beath High School - Int 1 Physics 14 A musician tunes a guitar by making the string t _ _ _ _ _ _ or looser. While playing the guitar, the note is changed by altering the l _ _ _ _ _ of string which vibrates. Changing the Note tighter length

Beath High School - Int 1 Physics 15 S _ _ _ _ strings produce a higher frequency than long strings. T _ _ _ _ strings produce a higher frequency than slack strings. Changing the Note Short Tight

Beath High School - Int 1 Physics 16 An organ produces a variety of musical notes which depend on the l _ _ _ _ _ of the air column which vibrates. The shorter pipes have the shorter air columns which produce the h _ _ _ _ _ frequency notes. Changing the Note length higher

Beath High School - Int 1 Physics17 Intermediate 1 Physics Sound and Music Speed of Sound

Beath High School - Int 1 Physics 18 During a thunderstorm, the lightning flash is seen a short time b _ _ _ _ _ the roll of thunder is heard. This is due to the fact that l _ _ _ _ travels much faster than sound through the air. Speed of Sound between light In air:Speed of light = m/s Speed of sound = 340 m/s

Beath High School - Int 1 Physics 19 (meaning; speed equals distance d _ _ _ _ _ _ by time) In a laboratory the speed of sound can be calculated using the formula below. Calculating the Speed of Sound divided

Beath High School - Int 1 Physics 20 Speed of Sound : Apparatus different

Beath High School - Int 1 Physics 21 A loud sound is made. As the sound reaches microphone A, the timer s _ _ _ _ _. When the sound waves reach microphone B, the timer s _ _ _ _. The distance between the microphones is measured with a m _ _ _ _ stick. The experiment can be r _ _ _ _ _ _ _ to calculate a more accurate, average result. Speed of Sound stops starts metre repeated

Beath High School - Int 1 Physics 22 Speed = distance/time = 1.0/ = m/s Example: Recorded times: s, s, s, s, s Average time = /5 = s Speed of Sound Distance travelled = 1 metre

Beath High School - Int 1 Physics23 Intermediate 1 Physics Sound and Music Using Sound

Beath High School - Int 1 Physics 24 A vacuum is an e _ _ _ _ space, so there are no particles to pass on the vibrations. The only thing that sound cannot pass through is a v _ _ _ _ _. Sound can travel through s _ _ _ _ _, liquids and g _ _ _ _. solids, Using Sound gases. vacuum. empty

Beath High School - Int 1 Physics 25 Some animals can detect higher frequency sounds than h _ _ _ _ _. When listening to music, you hear s _ _ _ _ _ with a wide range of frequencies. We can detect sounds that range from about 20 hertz to hertz. As we get o _ _ _ _, the upper limit gradually falls to about hertz. sounds Using Sound older humans.

Beath High School - Int 1 Physics 26 Sound beyond the u _ _ _ _ limit of human hearing ( Hz) is called ultrasound. Ultrasound can be used in hospitals to scan the b _ _ _ in the mother's womb. This can be used by a computer to produce an i _ _ _ _ ofthe baby on a screen. upper Using Sound - Ultrasound baby image

Beath High School - Int 1 Physics 27 A system called s _ _ _ _ is used by fisherman at sea. The ultrasound signal is transmitted towards the sea bed and an e _ _ _ is detected. Shoals of f _ _ _ are located by this method. sonar Using Sound - Ultrasound echo fish

Beath High School - Int 1 Physics 28 Sound level is measured in d _ _ _ _ _ _ _ (dB). The sound level of a noise means how l_ _ _ it is. The sound level varies depending on the source of the sound. loud Sound Levels decibels

Beath High School - Int 1 Physics 29 Sound l _ _ _ _ (dB) 130J _ _ engine at 50 metres 100Pneumatic d _ _ _ _ 70 Rush hour t _ _ _ _ _ _ 0 S _ _ _ _ _ _ level Sound Levels Jet drill traffic Silence

Beath High School - Int 1 Physics 30 When sound levels rise to unacceptable levels, the problem is described as n _ _ _ _ pollution. There are many sources of noise pollution, such as aircraft noise or pneumatic drills. Exposure to high sound levels over a long time can d _ _ _ _ _ our hearing. Listening through stereo headphones will produce a harmful effect if the v _ _ _ _ _ is turned to maximum. noise Sound Levels damage volume

Beath High School - Int 1 Physics31 Intermediate 1 Physics Sound and Music Amplified Sound

Beath High School - Int 1 Physics 32 A stereo system can be used to l _ _ _ _ _ to a compact disc (CD) or a radio programme. No matter what function is selected, the signal passes through an amplifier which turns a small amplitude electrical s _ _ _ _ _ into a higher amplitude one. listen Amplified Sound signal

Beath High School - Int 1 Physics 33 When announcements are made at airports and stations, the message has to be changed from sound into e _ _ _ _ _ _ _ _ _ signals and back to sound. Only the amplitude of the signal is changed. The frequency does n _ _ change. Amplified Sound not electrical

Beath High School - Int 1 Physics 34 When announcements are made at airports and stations, the message has to be changed from sound into e _ _ _ _ _ _ _ _ _ signals and back to sound. An electronic system of 3 parts is used to amplify the s _ _ _ _ given out by the announcer Amplified Sound electrical signal

Beath High School - Int 1 Physics 35 Part of the systemFunction m _ _ _ _ _ _ _ _ _ converts sound into an e _ _ _ _ _ _ _ _ _ signal a _ _ _ _ _ _ _ _ makes the electrical signal s _ _ _ _ _ _ _ (bigger amplitude) l _ _ _ _ _ _ _ _ _ _ converts the electrical signal back to s _ _ _ _ microphone Amplified Sound electrical amplifier stronger loudspeaker sound

Beath High School - Int 1 Physics 36 The performances of different amplifiers can be compared by finding the gain of the amplifier. Voltage Gain

Beath High School - Int 1 Physics 37 Example: Find the voltage gain of the following amplifier. Voltage Gain

Beath High School - Int 1 Physics 38 = 400 Voltage Gain N.B. Voltage gain is just a number. It has no u _ _ _. unit

Beath High School - Int 1 Physics 39 A recording of your own v _ _ _ _ will sound a bit strange when it is played back from a cassette. This is because we normally hear our own voice by: vibrations of bones in our s _ _ _ _ and vibrations in the air being detected by our e _ _ _ When we listen to a recording of our own voice we hear it by: vibrations in the a _ _ being detected by our ears only. Playback voice skull ears air

Beath High School - Int 1 Physics 40 A CD (compact disc) is a source of h _ _ _ quality sound. As the CD spins inside the CD player, light from a l _ _ _ _ reflects off the CD. There is no wear and tear of the disc surface and there is very little background n _ _ _ _. Playback high laser noise.

Beath High School - Int 1 Physics41 Intermediate 1 Physics Sound and Music End of Unit