An automobile starts from rest and accelerates to a final velocity in two stages along a straight road. each stage occupies the same amount of time. in stage 1, the magnitude of the car's acceleration is 2.8 m/s2. the magnitude of the car's velocity at the end of stage 2 is 2.6 times greater than it is at the end of stage 1. find the magnitude of the acceleration in stage 2.

The answer is a2 = 4.48 m/s2

Explanation:

Let´s start with the equations we know:

Where:

Now, let´s divide the problem in Stage 1 and 2 and get equations for each stage:

Stage 1 knowns and unknowns:

Stage 1 equation:

Stage 2 knowns and unknowns:

Stage 2 equation:

Now we can substitute the resultant equation from stage 1 into stage´s 2 equation:

We can see "t" is on both sides, so it cancels out and we are left with:

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