What is the velocity and position of a bus after a given time?

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The discussion revolves around calculating the velocity and position of a bus given its acceleration function a(t) = alpha t, with alpha set at 1.13 m/s^3. For Part A, the user attempts to find the bus's velocity at t_2 = 2.15 s using the equation Vf = Vo + at but encounters errors in their calculations. The response emphasizes that the user should correctly apply the time difference in their calculations and suggests using the appropriate kinematic equations for each part. For Part B, it is highlighted that a different equation is necessary to find the position, as it involves integrating the acceleration over time. Clarifying these points can help resolve the user's confusion and lead to accurate results.
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Homework Statement


The acceleration of a bus is given by a (t)= alpha t, where alpha = 1.13 m/s^3 is a constant.

Part A) If the bus's velocity at time t_1 = 1.01 s is 4.93 m/s, what is its velocity at time t_2 = 2.15 s?

Part B) If the bus's position at time t_1 = 1.01 s is 6.01 m, what is its position at time t_2 = 2.15 s?

Homework Equations



Vf = Vo + at

The Attempt at a Solution


I am stuck on Part A and Part B. I am applying the Vf = Vo + at equation. I set it up as
Vf = 4.93 + (alpha * t)(2.15s)

and the answer that I get is wrong. Anyone have any idea how to approach this? Thanks.
 
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Your equation that you are using for part (A) is correct, perhaps if you showed us your numbers we could point out what's going wrong. However, note that part (B) us asking for position, so you need a different kinematic equation.
 
Remember to take the difference of the two times when using v(1.01) as Vo in the equation. It is a very common mistake.

The real equation: Vf = Vo + a(tf-to) for constant a.
 
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