I think it was about a week ago or so that I declared chapter two of University Physics, by Young and Freeman, dead. I had been sauntering through it for months. The main points are easy, although as usual the application of them into concrete situations is more diffiicult. But here I summarize the main points:
1. Average velocity Δx/Δt or (x2-x1)/(t2-t1).
2. Instantaneous velocity is lim Δt→0 of Δx/Δt, which = dx/dt.
3. Average acceleration Δv/Δt or (v2-v1)/(t2-t1).
4. Instantaneous acceleration is lim Δt→0 of Δv/Δt, which = dv/dt.
Then these equations work for constant acceleration
5. v2 = v1 + at
6. x2 = x1 + vt + ½at2
7. v22 = v12 + 2a(x2-x1)
8. x2 - x1 = [(v2 + v1)/2]t
9. Finally, for varying acceleration, one will have to integrate:
x2 = x1 + ∫0→t of v dt
v2 = v1 +∫0→t of a dt
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