A body moving at 8 m/s accelerates uniformly at 3 m/s² for 7 s. What is its final speed?
Answer and explanation
Correct answer: B. 29 m/s
- Step 1: Use v = u + at. Step 2. v = 8 + 3 × 7 = 29 m/s. Answer: 29 m/s. Why not the others: 21 m/s is what you get if you forget the initial speed. 11 m/s is what you get if you forget to multiply the acceleration by time. 59 m/s is what you get if you multiply the initial speed by time.
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