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**1. Homework Statement**

The a-s graph for a rocket moving along a straight horizontal track has been experimentally determined. If the rocket starts from rest, determine its speed at the instants s = 20m, 50m, and 70m, respectively. On the graph, S1 = 50m, a1 = 10 m/s^2, S2 = 70m, and a2 = 20 m/s^2

**2. Homework Equations**

ads = vdv

ads = vdv

**3. The Attempt at a Solution**

I know that the solution for the velocity at S2 = 70m is V = 40 m/s, but I'm not sure how to get there.

I know we talked about the relationship for ads = vdv so I tried taking the integral on both sides to calculate for the velocity.

I tried to solve for the velocity at S2

The integral from 0 to v of vdv = the integral from 0 to 20 of ads

So, V^2/2 = 20s which means V^2 = 40s where S = 70 meters.

So I get V = √(40)(70) = 52.9, which is not correct.