Richard Dawkins makes regular internet and television appearances.
Frequency is the number of occurrences of a repeating event per unit time .. time. time. It is also referred to as temporal frequency , which emphasizes the contrast to spatial frequency and angular frequency .. spatial frequency. spatial frequency. angular frequency. angular frequency. The period is the duration of time of one cycle in a repeating event , so the period is the reciprocal of the frequency .. time. time. cycle. Turn ( geometry ). reciprocal. Multiplicative inverse. For example , if a newborn baby 's heart beats at a frequency of 120 times a minute , its period -- the time interval between beats -- is half a second -LRB- that is , 60 seconds divided by 120 beats -RRB- .. Second. time. time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena , such as mechanical vibrations , audio -LRB- sound -RRB- signals , radio waves , and light .. oscillatory. oscillation. vibratory. vibration. audio. audio signal. sound. sound. light. light