Check My Work: 100kg Mass Moving in a Straight Line

AI Thread Summary
A 100 kg mass is influenced by a force F(t) = (120 N/s)t + 4000 N, and its speed at t = 5 s is being calculated. The initial calculation yields a force of 4600 N at t = 5 s, leading to a speed of 230 m/s using the formula V = (FΔT)/M. However, there is a discussion about whether to use the maximum force during the interval or the average force for a more accurate result. The importance of balancing change symbols in equations is emphasized, suggesting that using average force could provide a better understanding of the mass's motion. The conversation highlights the need for careful consideration in applying physics principles to ensure accurate calculations.
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I was wondering if someone could check my work and see if its correct.

An object of mass 100.00kg moves in a straight line under the influence of a force given by F(t)=(120 N/s)t+4000N
At t=0 it is moving at 0 m/s. Determine its speed at t=5.00 s

What i did is this. I plugged 5s into the function and got 4600N. Then i used F▲V=M▲V arranged to V=(F▲T)/M
V=(4600N X 5.00s)/100.0kg
V=230. M/S

Thank you
 
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\int_{0}^{5} (120t + 4000)dt = m \int_{0}^{v} dv
 
I hope that you meant F ▲t = m ▲v ... which DOES lead to ▲V = (F▲t)/m .
. . . ("change" symbols in an equation should ALWAYS balance) . . .

But why would you use the strongest Force in the 5-second duration?
Why not use the weakest Force, instead? . . . why not use the AVERAGE ?
. . . (ALWAYS multiply one's full range by the other's average) . . .
 

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