160 140 120 100 Label the decibel scale distance (m) 80 60 40 speed (m/s) The speed of sound in air is about… ____ m/s The speed of sound is faster in different materials. On the graph above, label; Water, Steel, Concrete, air at 30 C and air at 0 C. Which state of matter does sound travel fastest through? Sound 20 0 time (s) small 600 5 aeroplane jet fighter 900 2 cheetah 50 2. 5 meteorite 10 000 0. 35 Which of these travel faster than the speed of sound in air? Fill in the answers in the table. speed of sound (m/s) decibels What causes sound? Sounds are made when___________ Label the following; frequency, amplitude and wavelength. Give a definition for each: Frequency: Amplitude: Wavelength: solid liquid gas Explain what happens with the bell jar to the ringing clock. Draw the sound waves on the clock that contains air.
Label the above oscilloscope reading quiet sound and loud sound. Label below; high pitch and low pitch. 1. What is a reflected sound called? 2. Are hard or soft surfaces best at reflecting sound? 3. Why are there soft materials on the walls of cinemas and theatres? 4. Name two animals that use echoes for navigation or communication. 6 4 1 What is the hearing range of a healthy young person? 2 How does the Ear hear? Label the diagram 3 5
