For t≥0, a particle has acceleration a(t)=t²-3t-4 m/s². When is the acceleration zero?
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For t≥0, a particle has acceleration a(t)=t²−3t−4 m/s². When is the acceleration zero?

G1 Physics · Accepted Answer

Set a=0: t²−3t−4=(t−4)(t+1)=0. Roots are 4 s and −1 s. Only t=4 s lies in the physical domain t≥0.