| What is sound caused by? | Vibrations |
| How does sound travel through a substance? | Sound wave causes particles to vibrate and knock into each other, which travels sound energy through the air. |
| What type of wave is sound? | Longitudinal |
| What is the frequency of a wave? | Number of waves produced per second |
| What is the amplitude of a wave? | The distance from centre of a wave to the crest or trough. |
| What is amplitude measured in? | Metres |
| What is frequency measured in? | Hertz (Hz) |
| What is the relationship between the pitch and the frequency of a sound? | The higher the frequency of a sound, the higher the pitch. |
| What is the range of human hearing? | 20-20,000Hz |
| What is the relationship between the amplitude of a sound and the volume? | The higher the amplitude of a wave, the higher the volume of the sound. |
| Is the wave high or low frequency? | High Frequency |
| Is this wave high or low frequency? | Low frequency |
| What type of wave is this? | Longitudinal Wave |
| What type of wave is this? | Transverse Wave |
| What is a longitudinal wave? | A wave in which its particles move in the same direction as the direction the wave is travelling. |
| What is the speed of sound in air? | 340ms^-1 |
| What is the formula for measuring the speed of sound? | V=d/t |
| What does "V" represent in the formula "V=d/t" | Speed |
| Describe the method of recording the speed of sound using blocks of wood, a trundle wheel and a timer. | Two people stand at least 50 metres apart, (measured with a trundle wheel), one holds blocks of wood and the other holds a timer. The first person will hit the blocks of wood together, and when the other person sees the objects collide, they start the timer. When they hear the sound made, they stop the timer. They can then use v=d/t to calculate the speed of sound. |
| Describe the process of recording the speed of sound in a lab with two microphones and an electronic timer. | Place two microphones 1 or 2 metres away from each other. Make a noise in one microphone, this will start the electronic timer. When the sound reaches the second microphone, the timer will stop. You can then use v=d/t to calculate the speed of sound. |
| How do you convert milliseconds (ms) to seconds (s) | Replace the prefix 'milli' with x10^-3 |
| What is 40ms in seconds? | 40 x 10^-3 seconds |
| What is 0.03ms in seconds? | 0.03x10^-3 seconds |
| Calculate the speed of sound from this graph. | 0.34013605442ms^-1 |
| What is a medium? | A material sound can travel through. |
| In what state of matter does sound travel fastest in? | Solids |
| Why does sound travel fastest in solids? | The particles are closer together, so the vibrations can pass through the medium more easily. |
| What is used to measure the loudness of a sound? | A sound/decibel meter |
| What is sound level measured in? | Decibels (dB) |
| What is the sound level of complete silence? | 0dB |
| What is the sound level of the threshold of pain? | 120dB |
| What is 'noise'? | Unwanted sounds we hear in day to day life |
| Give an example of noise. | Dogs barking, machinery, traffic |
| Define the term 'noise pollution' | Unwanted noise that is too loud or lasts too long, which causes problems |
| Give examples of noise pollution | Airport noise, construction work, washing machines |
| What is ultrasound? | Sound above 20,000Hz |
| What are some uses of ultrasound? | Body scans, seeing unborn children, breaking up kidney stones through vibrations, animals using 'echolocation' to detect predators and prey. |
| What is infrasound? | Sound under 20Hz |
| What are some uses of infrasound? | Volcano detection, tracking meteors, animal communication |
| How do you calculate the distance of an echo? | Use v=d/t, but either half final answer or half 't'. |
| A person claps their hands, producing a noise. The person hears the noise 0.2 seconds later, after it has reflected off a wall as shown. How far away is the wall? | 34 m |
| What is the formula for calculating frequency when given the number of waves and the time? | f = N/t |
| In the formula f=N/t, what is f? | Frequency in Hz |
| In the formula f=N/t, what is N | Number of waves (no unit) |
| In the formula f=N/t, what is t? | Time in seconds |
| What is the formula for calculating speed, when given the frequency and wavelength. | v = f λ |
| In the formula v = f λ, what is v? | Speed in ms^-1 |
| In the formula v = f λ what is f? | Frequency in Hertz |
| In the formula v = f λ, what is λ? | Wavelength in metres |
| What is sampling? | The process of turning a sound wave into a digital signal |
