Engineering Board Exam Reviewer · Rectilinear Motion: Velocity and Acceleration · medium
A particle's position is s=t3-6t2+9t meters. Find the total distance traveled during the first 4 seconds.
- 4 m
- 12 m
- 8 m
- 16 m
Answer
B. 12 m
Solution
v=3t2-12t+9=3(t-1)(t-3), so the particle reverses at t=1 and t=3. s(0)=0, s(1)=4, s(3)=0, s(4)=4. Distance =4+4+4=12 m (the displacement is only 4 m).
More Rectilinear Motion: Velocity and Acceleration questions
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