1) Sounds are produced by a) vibrations b) movements of objects 2) What do the dots represent? a) Sound particles b) Air particles 3) Which waveform has a high pitch? a) The left waveform b) The right waveform 4) The range of sound waves which can be heard by humans is called a) Audible range b) Amplitude range 5) The humans' ''Audible range'' a) 20,000 to 200,000 Hz b) 20 to 20,000 Hz 6) Sound waves which have a frequency that is above 20,000 Hz is called  a) Ultraviolet waves b) Ultrasound waves 7) List the animals which can hear ultrasound waves a) Easy! b) Correct! 8) A high pitch sound a) Whistle b) Drums 9) A low pitch sound a) Whistle b) Drums 10) Fill in the diagram a) Easy! b) Done! 11) Fill in the diagram a) Easy! b) Done!

Physics-ch.13

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