A car moving with an initial velocity of 25 mis north has a constant acceleration of 3 m/s2 south. After 6 s its velocity will be:
Correct answer: A. 7 m/s north
- A. 7 m/s north
- B. 43 m/s north
- C. 7 m/s south
- D. 20 m/s north
Explanation
The final velocity of the car can be calculated using the equation: vf = vi + a·t, where vi is the initial velocity, a is the acceleration, and t is the time.Given: vi = 25 m/s north, a = -3 m/s2 (since it's south), and t = 6 s.Substitute these values into the formula: vf = 25 + (-3) * 6 = 25 - 18 = 7 m/s north.Therefore, the correct answer is 7 m/s north.Option B assumes an increase in velocity, which is incorrect because the acceleration is in the opposite direction. Option C suggests a reversal in direction, which hasn't occurred in the given time frame. Option D underestimates the effect of the opposing acceleration.
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