An object moves with initial speed 4 m/s and constant acceleration 4 m/s^2. How far does it travel in 3 s?
Answer and explanation
Correct answer: C. 30 m
- Step 1: Use s = v0 t + (1/2) a t^2.
- Step 2: s = 4 x 3 + 0.5 x 4 x 3^2 = 30 m.
Answer
30 m.
Why not the others: Forgetting the factor 1/2, using the final speed for the whole time, or leaving the time unsquared produces the other distances.
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