An elevator filled with passengers has a mass of 1700 kg...

...a) the elevator accelerates upward from rest at a rate of 1.2m/s2 for 1.5s. Calculate tension.

I got the answer correct for this, by doing mg+ ma= 1700*9.8 + 1700*1.2= 18700N

b) The elevator continue upwards at constant velocity for 8.50s. What is the tension in the cable during this time?

This is where I'm stuck. How is time related to tension? Does it have anything to do with vf=vi + at or am I completely wrong?

Thanks so much!

b) the tension in the cable during this8.5s
= 1700*9.8 + 1700* 0= 16660N
answer

BINGO!!

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Hmmm....U seem to have accepted the time = 1.5 s in part a)
and got the correct answer with out using this time.

so why be bothered by it in part b)?
In part b) there is no acceleration added or subtracted from "g" when the elevator moves at constant speed, so the tension in the cable would be the same in this part as if elevator were not moving at all.