Two New Sciences motion and a naturally accelerated vertical motion which produces a parabolic curve. Two motions at right angles can be calculated using the sum of the squares. He shows in detail how to construct the parabolas in various situations and gives tables for altitude and range depending on the projected angle. [274] Air resistance shows itself in two ways: by affecting less dense bodies more and by offering greater resistance to faster bodies. A lead ball will fall slightly faster than an oak ball, but the difference with a stone ball is negligible. However the speed does not go on increasing
Augmentative and alternative communication Rate enhancement strategies can increase the user's rate of output to around 12–15 words per minute, and as a result enhance the efficiency of communication. There are two main options for increasing the rate of communication: encoding and prediction. Encoding is a technique permitting an AAC user to produce an entire word, sentence or phrase using only one or two activations of their AAC system. In numeric, alpha-numeric, and letter encoding (also known as abbreviation-expansion), words and sentences are coded as sequences of letters and numbers. For example, typing "HH" may retrieve "Hello, how are you?". In iconic encoding strategies,