Engineering Board Exam Reviewer · Applications: Newton's Second Law and Motion · medium
A boat decelerates due to water resistance according to dv/dt=-0.5v, with initial velocity 20 m/s. Find the velocity after 4 seconds.
- 2.71 m/s
- 5.00 m/s
- 10.0 m/s
- 1.35 m/s
Answer
A. 2.71 m/s
Solution
v=20e-0.5(4)=20e-2 2.71 m/s.
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