Engineering Board Exam Reviewer · Engineering Mechanics · medium
An object starts from rest and slides down a frictionless slope, descending a vertical height of 7 m. Using conservation of energy, what is its speed at the bottom? (g = 9.81 m/s2)
- 68.67
- 8.29
- 11.72
- 137.34
Answer
C. 11.72
Solution
By conservation of energy, mgh = 1/2mv2, so v = sqrt(2gh) = sqrt(2 × 9.81 × 7) = 11.72 m/s.
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