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| style="height:20px; width:200px; text-align:center;" |The [[frequency]] of this [[wave]] can be found by counting the number of times the red marker oscillates [[oscillate]]s every [[second]].

: f = [[frequency]]: T = [[Period|time period ]] (the [[time ]] it takes for one [[wave]] to pass a point). ==Key Stage 4=====Meaning===[[Frequency]] is the number of [[wave]]s that pass a given point in one [[second]]. ===About Frequency===: [[Frequency]] is [[measure]]d in [[Hertz]] ([[Hz]]).{| class="wikitable"|-| style="height:20px; width:200px; text-align:center;" |'''Water Waves'''|-|[[File:WaveFrequency.gif|center]]|-| style="height:20px; width:200px; text-align:center;" |The [[frequency]] of this [[wave]] can be found by counting the number of times the red marker [[oscillate]]s every [[second]].|}: The higher the [[frequency]] the quicker the [[wave]] [[Oscillation|oscillates]].: In [[sound]] [[frequency]] is known as [[pitch]]. A high [[pitch]] is a high [[frequency]].: In [[light]] [[frequency]] affects the [[colour]] of the [[light]]. Red is a low [[frequency]] and violet is a high [[frequency]].: [[Frequency]] can be found by counting the number of [[wave]]s which pass a point in a given [[time]] and dividing this by the [[time]]. ===Equation===''NB: You do not need to remember these equations but you should know how to find [[frequency]] given the number of waves passing a point and the time taken.'' ====Equation 1====Frequency = 1/(Period) <math>f = \tfrac{1}{T}</math> Where:f = [[Frequency]] T = [[Period|time period]] (the [[time]] it takes for a wave to pass a point). ====Equation 2==== Frequency = (Number of Waves which pass a point)/(Time taken for waves to pass a point) <math>f = \tfrac{n}{t}</math> Where:f = [[Frequency]] n = Number of [[wave]]s which pass a point. t = The [[time]] taken for those [[wave]]s to pass a point. ===Example Calculations==={| class="wikitable"| style="height:20px; width:200px; text-align:center;" |A scientist wants to determine the [[frequency]] of a [[pendulum]]. They count that the [[pendulum]] [[oscillate]]s 15 times over 20 seconds. Calculate the [[frequency]] of the [[pendulum]].| style="height:20px; width:200px; text-align:center;" |A sailor notices a buoy bounce up and down 24 times over a minute. Calculate the [[frequency]] of the [[wave]]s.|-| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities''' n = 15 t = 20s| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities''' n = 24 t = 60|-| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].''' <math>f = \tfrac{n}{t}</math> <math>f = \tfrac{15}{20}</math> <math>f = 0.75Hz</math> | style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].''' <math>f = \tfrac{n}{t}</math> <math>f = \tfrac{24}{60}</math> <math>f = 0.4Hz</math>|}