Physics 4A Lecture 2: Jan. 8, 2015 Sunil Sinha UCSD Physics Using Calculus v = dx / dt
a = dv / dt = d 2 x / dt 2
v = ∫ a dt = at + C = v0 + at
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x = ∫ v dt = ∫ (v0 + at)dt = v0 t + at + C = x0 + v0 t + at
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Go to the wikipedia site on this, hFp://en.wikipedia.org/wiki/Galileo's_Leaning_Tower_of_Pisa_experiment and there is an embedded video of this experiment being done by a US astronaut on the surface of the moon!! A: Yes B: No MulUplying Vectors •  Scalar Product of 2 vectors •  Vector Product of 2 vectors Pop quiz: If I want the angle between 2 vectors, it is enough to know: •
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A: Their Scalar Product B: Their Vector Product C: Either of the above D: Both of the above Which of the following is a unit vector? •
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A: i.j B: i x i C: i x j D: i + j + k