Engineering Board Exam Reviewer · Rectilinear Motion: Velocity and Acceleration · easy
A particle moves along a line with position s=t3-6t2+9t meters. Find its velocity at t=2 s.
- 3 m/s
- -3 m/s
- -9 m/s
- 9 m/s
Answer
B. -3 m/s
Solution
v=ds/dt=3t2-12t+9. At t=2: v=12-24+9=-3 m/s.
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