Safety engineers estimate that an elevator can hold 20 persons of 75kg average mass. The elevator itself has a mass of 500kg. Tensile strength tests show that the cable supporting the elevator can tolerate a maximum force of 29600 N. What is the greatest acceleration that the elevator's motor can produce without breaking the cable?(adsbygoogle = window.adsbygoogle || []).push({});

The answer to the question is listed as 4.8 m/s/s.

Here's what I'm comming up with (and i can't get superscripts working which should explain the odd formatting):

m(elevator) = 500kg

m(people)= 75kg x 20 = 1500 kg

m(total)=500kg + 1500kg = 2000kg

F = m/a so a=F/m

29600N/2000kg = a

14.8 m/s/s = a

I'm really not sure where I'm going wrong here, it seems simple enough...

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# Homework Help: Forces involved in an elevator

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