A car starts at 10 m/s and accelerates uniformly at 2 m/s^2 for 6 s. What is its final speed?
Answer and explanation
Correct answer: D. 22 m/s
- Step 1: For uniform acceleration, v = v0 + a t.
- Step 2: v = 10 + 2 x 6 = 22 m/s.
Answer
22 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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