If we record the ground motion at a single location for a range of time, we can measure the time between peaks in the motion, which we call the wave period. Another important term is frequency, which is the inverse of the period, or one divided by the peak-to-peak time between wave crests.
The Universities and Colleges Admissions Service (UCAS) is a UK-based organisation whose main role is to operate the application process for British universities.
UCAS Extra is a way of applying to additional universities if you have either received no offers from your original five choices, or if you have changed your mind. See also the FAQ 2014 thread here.his year, UCAS Extra runs from 25 February 2014 to 2 July 2014. Remember that you can't use Extra unless you hold no offers, so you can only apply after you have declined all that you did receive, and/or withdrawn from any choices for which you haven't had a decision.