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Home Vectors Vector Derivatives Corollary |
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Corollary
COROLLARY Suppose X = F(t) is a curve whose distance |F(t)| from the origin is a constant r0. Then the derivative F'(t) is perpendicular to F(t) whenever F'(t) ≠ 0. PROOF We use the Inner Product Rule. For all t,
Therefore F(t) · F'(t) = 0, so F(t) ⊥ F'(t), as shown in Figure 10.7.6.
Figure 10.7.6 We see from the corollary that if a particle moves with constant speed |V| = v0, then its acceleration vector is always perpendicular to the velocity vector (Figure 10.7.7).
Figure 10.7.7 Motion with Constant Speed
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Home Vectors Vector Derivatives Corollary |
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