and described by the formula: where A is the amplitude of oscillation, f is the frequency, t is the elapsed time, and is the phase of the oscillation. The phase determines or is determined by the initial displacement at time t = 0. A motion with frequency f has period. Two potential ambiguities can be noted:
Incubation Period Shingles is not transmitted from exposure to another infected person so there is no applicable incubation period. Anyone who has recovered from varicella may develop shingles. Mode of Transmission Transmission of the virus occurs through direct contact with the rash or fluid from the lesions.
Rubella is contagious but less so than measles and chickenpox. How long does it take to show signs of rubella after being exposed? The incubation period varies from 12 to 23 days (av-erage, 14 days). Symptoms are often mild and may be subclinical or inapparent up to half of the time.