A wave's frequency is the number of cycles that are completed in a certain amount of time. The symbol for frequency is the lowercase f and we measure it in cycles per second, which is the same as the unit hertz. A wave with a frequency of 20 Hz completes 20 wave cycles every second.Be careful that you don't confuse frequency with period. This is a common mistake. wave is a disturbance that travels through a medium in a periodic fashion, carrying energy without transporting matter. Waves are described and measured by five wave parameters: the period, the frequency, the amplitude, the wavelength, and the speed.
Quick Answer. It takes three to five hours for the effects of novocaine and other local dental anesthetics to wear off completely, according to Jonathan G. Campbell, D.D.S. The tooth remains numb for one to two hours, while the tongue and lips remain numb for up to five hours. Continue Reading.
Dysport (like Botox) starts to wear off after a few months in most cases. We wish it would last longer than 3-4 months in most cases but since you are not happy with the results, then a few months is all you have to wait. Many patients don't get an eyebrow lift with the botox or dysport an this is not uncommon. April 1st, 2011.