1. Grab the nearest book.
2. Open the book to page 23.
3. Find the fifth sentence.
4. Post the text of the sentence in your journal along with these instructions.

In symbols, the average acceleration a, over a time interval Δt = t₂ - t₁ during which the velocity changes by Δv = v₂ - v₁, is defined as
a = (v₂ - v₁)/(t₂ - t₁) = Δv/Δt.

Douglas C. Giancoli - Physics for Scientists & Engineers

Via Dunkle Zeiten.