Use the wave equation to link speed, frequency and wavelength. See how graphs, units and rearranging formulas help you solve GCSE Physics questions about different kinds of waves.
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You can find more about this topic by visiting BBC Bitesize - Properties of waves - AQA
One Hz = one wave passing per second. Gauss are the units of magnetism and wave-seconds don't exist
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The normal range of human hearing is 20 Hz to 20 kHz. The frequency tells you how many waves reach a given point (or go past an observer) in a second
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You need to rearrange the wave equation to ë = v/f
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Working with powers of ten can be tricky. Make sure you do a rough calculation using the powers of ten so that you know if your final answer is in the right area
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The difference between the last two answers is the units - mhz is wrong because the capitalisation is incorrect. As well as checking that you can rearrange the wave equation, it tests if you are aware of the correct way to write units
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Did you get the rearranged equation the correct way up?
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When dealing with complex questions like this, you need to break them down into smaller steps. To do that, start from the equation you need to work out the speed v = fë. You have the frequency and need the wavelength. So you then look at the other information to see how you can work out the wavelength from the data. Once you have that, it is a simple matter of plugging the figures into the equation
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You will see various different values for the speed of sound because it varies according to the air pressure
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This is a wavelength question, but slightly disguised! We didn't give you the speed of the waves because, by now, you should know that microwaves travel at the same speed as all electromagnetic waves - 3 x 108 m/s. That is actually the speed they travel in a vacuum but it isn't much different in other media
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A nice easy finish for you, hopefully you did this one using mental arithmetic - 1.8 (m/s) divided by 0.9 (m). Mental arithmetic can save time in the exams but is not always possible
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