What is the tension on the line when the elevator is accelerating

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superdave
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An elevator weighs 10000N. What is the tension on the line when the elevator is accelerating upwards at 3 m/s?

I don't know how to go about this one. Any help?
 
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Well, acceleration is in [itex]\frac {m}{s^2} [/tex]. Is that a typo? Also, what is Newtons first law?[/itex]
 
And after you recall Newton's first law, be sure to draw a force diagram before solving the problem. This will help ensure that you get the signs correct (arrows pointing in opposite directions will have opposite signs).
 
sporkstorms said:
And after you recall Newton's first law, be sure to draw a force diagram before solving the problem. This will help ensure that you get the signs correct (arrows pointing in opposite directions will have opposite signs).

I agree with drawing a free body diagram (this should always be the first step in that type of question) but I think that everybody meant Newton's *second* law...

Patrick
 
superdave said:
An elevator weighs 10000N. What is the tension on the line when the elevator is accelerating upwards at 3 m/s?

I don't know how to go about this one. Any help?

I'm sorry to be pedantic but the units of acceleration are not [itex]m/s[/itex], they are [itex]m/s^2[/itex].

There are two questions that you should ask yourself when doing this question;

(1) What is the tension in the wire when the elevator is stationary? I.e. what force is required to balance the weight of the elevator?

(2) What additional force is required to accelerate the elevator at [itex]3 m/s^2[/itex]? Hint: For this one you will need to use Newton's second law as nrqed said.

Hope this helps
-Hoot:smile:
 
nrqed said:
but I think that everybody meant Newton's *second* law...

Whoops. I was like a sheep, following right over the edge of a cliff.