Hello!
Find the change in velocity by finding the area under the line in an acceleration v. time graph:
We can divide the area underneath the interval 1 - 2 seconds into a rectangle and a triangle. Use the formulas:
A = l × w
A = 1/2(b · h)
We can solve for the rectangle first:
A = 2 × 1 = 2
Do the remaining area using the formula for a triangle:
A = 1/2 (2 · 2) = 2
Add the areas together:
2 + 2 = 4 m/s.
The Δv (change in velocity) is 4 m/s.