At a recent checkup, I was shocked: Even though I was eating foods rich in saturated fat and a seemingly more indulgent diet, my total cholesterol was down 10 points, my bad LDL cholesterol was stellar, and my good HDL was the highest it's ever been.
As the frequency of the signal to be measured increases to approach the frequency of the source frequency, measurement error increases. To improve the accuracy of the frequency measurement for higher unknown frequency, we can use this second measurement method, count number of pulses in known time.
Frequency and period are used to measure properties of waves (e.g. sound, light, ocean waves) as well as other predictable events. Events that happen aperiodically but with a predictable average rate (such as radioactive decay) are often measured in Bequerels (Bq).