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A bus accelerates at -0.5 m/s2 for 12.5 seconds . If the bus had an initial speed of 31 m/s, what is its new speed? A. 12.25m/s B. 37.25m/s C. 24.75m/s D. 6.25m/s

User EdwardM
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Final answer:

To find the new speed of the bus after acceleration, the initial speed is added to the product of acceleration and time. The bus decelerates from an initial speed of 31 m/s at a rate of -0.5 m/s² for 12.5 seconds, resulting in a new speed of 24.75 m/s, answer C.

Step-by-step explanation:

The student's question is concerned with calculating the new speed of a bus after a period of acceleration. To find the new speed, we use the formula for acceleration, which is defined as the change in velocity over time:


Final velocity (v) = Initial velocity (u) + Acceleration (a) × Time (t)


Given:

Initial speed (u) = 31 m/s,

Acceleration (a) = -0.5 m/s² (since it's decelerating),

Time (t) = 12.5 seconds.


To calculate the new speed, plug the given values into the formula:


v = u + (a × t)

v = 31 m/s + (-0.5 m/s² × 12.5 s)

v = 31 m/s - 6.25 m/s

v = 24.75 m/s


The correct answer is: C. 24.75 m/s. The bus's new speed after accelerating for 12.5 seconds is 24.75 m/s.

User Danosaure
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