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→Example Calculations
===Example Calculations===
====Finding Frequency from Time Period====
{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |Calculate the [[frequency]] of a [[wave]] with a [[period]] of 0.04 seconds.
| style="height:20px; width:300px; text-align:center;" |A giant pendulum takes 16 seconds to make one complete [[oscillation]]. Calculate the [[frequency]] of the [[pendulum]].
|-
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
T = 0.04s
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
T = 16s
|-
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math> f = \frac{1}{T}</math>
<math> f = \frac{1}{0.04}</math>
<math> f = 25Hz</math>
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math> f = \frac{1}{T}</math>
<math> f = \frac{1}{16}</math>
<math> f = 0.0625Hz</math>
|}
====Finding Frequency from the number of waves and time taken====
{| class="wikitable"
| style="height:20px; width:300px; 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]].
<math>f = 0.4Hz</math>
|}
====Finding Frequency from Wavelength and Wave Speed====
{| class="wikitable"
| style="height:20px; width:200px; text-align:center;" |A [[microwave]] travelling at a speed of 3.0x10<sup>8</sup>m/s has a [[wavelength]] of 0.051m. Calculate the [[frequency]] of the [[wave]] correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:200px; text-align:center;" |An [[ultrasound]] [[wave]] of [[wavelength]] 0.125m passes through an [[Iron]] block at a [[speed]] of 5000m/s. Calculate the [[frequency]] of the [[wave]] correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
v = 3.0x10<sup>8</sup>m/s
λ = 0.051m
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
v = 5000m/s
λ = 0.125m
|-
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math> f = \frac{v}{\lambda}</math>
<math> f = \frac{3.0 \times 10^8}{0.051}</math>
<math> f = 5882352941Hz</math>
<math> f \approx 5900000000Hz</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math> f = \frac{v}{\lambda}</math>
<math> f = \frac{5000}{0.125}</math>
<math> f = 40000Hz</math>
|}