Tackling Difficult Homework Integrals

Thread starter nysnacc
Start date Oct 14, 2016
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Homework Integrals

AI Thread Summary

The discussion revolves around solving a homework problem involving integrals related to impulse and force. The integral presented is ∫ T - mg dt, where T is defined as 100 + 2t². The user encountered confusion regarding the units, realizing that both T and mg need to be in kilonewtons (kN) for consistency. The issue of obtaining a negative impulse was raised, highlighting the importance of unit consistency in calculations. Ultimately, ensuring all units align is crucial for accurate results in physics problems involving integrals.

Oct 14, 2016

nysnacc

Homework Statement

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 ...??

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Oct 15, 2016

haruspex

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nysnacc said:

T=100+2t²

... where the units are ...?

Oct 18, 2016

nysnacc

Oh I see 100+ 2t^2 in KN... mg should also in kN

Oct 18, 2016

haruspex

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nysnacc said:

Oh I see 100+ 2t^2 in KN... mg should also in kN

Whatever makes all the units consistent.

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