Negative impulse from tension and weight integral

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nysnacc
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Homework Statement


Screenshot of a Mastering Physics problem 16.3 showing text about a 9000 kg helicopter with thrust T = 100 + 2t^2 kN, a helicopter photo, and an answer box asking for the linear impulse from t = 0 to t = 3.20 s.


Homework Equations


∫ F dt = mv

The Attempt at a Solution


I have
∫ T -mg dt
= ∫ 100+2t2 - mg dt
= ∫ 100-9000*9.81 +2t2 dt

but then I got negative impulse ...??
 
nysnacc said:
Oh I see 100+ 2t^2 in KN... mg should also in kN
Whatever makes all the units consistent.