A test rocket is launched vertically from ground level (y=0m), at time t=0.0 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 97 m and acquired a velocity of 40 m/s. The rocket continues to rise in upward flight, reaches maximum height, and falls back to the ground. What is the upward acceleration of the rocket during the burn phase?

2 answers

Assuming constant acceleration:
use the kinematic equation Vf^2=Vo^2+2ad
there is no Vo, so the equation becomes: Vf^2=2ad
substitute and you get: 40^2=2a(97)
solve for a: a= 8.25 m/s or 8.3 m/s if you use sig. figs.

Hope this helps!
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