A car starts at 5 m/s and accelerates uniformly at 3 m/s^2 for 3 s. What is its final speed?
Answer and explanation
Correct answer: C. 14 m/s
- Step 1: For uniform acceleration, v = v0 + a t.
- Step 2: v = 5 + 3 x 3 = 14 m/s.
Answer
14 m/s.
Why not the others: The other values leave out the initial speed, add the data instead of multiplying, or count one extra second.
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