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## Physics question

A man standing on a scale in an elevator that is moving upwards will always have an apparent weight (on the scale) greater than his normal weight.
True or false?

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Incomplete problem.

Does the escalator move at a constant speed? If so, there will be no change in the scale.

If the escaltor accelerates while moving up, then there is an increase in the man's weight.

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A falling object that has reached terminal velocity is in equilibrium.
T or F

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F ?

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well that was the right answer, you can have motion without acceleration

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Originally posted by dreamHOBO
False...It would be less
If the elevator is moving up, then the apparent weight will increase.

If the elevator is moving down, then the apparent weight will decrease. In fact, if the man is doing free fall, then the scale will read zero.

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I'm no longer participating in this thread. Hopefully others too.

I'm not going to do your homework! You need to struggle yourself and understand the reasons for your answers.

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Originally posted by epgs

A falling object that has reached terminal velocity is in equilibrium.
T or F
Dynamic equilibrium, yes, correct.

Now I leave it to you to figure out how to prove it

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Originally posted by cyansmoker
Dynamic equilibrium, yes, correct.

Now I leave it to you to figure out how to prove it
I believe dynamic equilibrium usuall refers to something more like this:

AgI(s) <-> Ag+(aq) + I-(aq)

Instead of a <->, there should be a symbol of an arrow poitning left on top of an arrow pointing right, that is the symbol for equilibrium.

But, yes what you describe is also dynamic equlibrium, which in itself is a necessity for equilibrium, which is often defined as ...a dynamic condition, in which a system doesnt appear to be changing, but is constantly changing. In each case, the forward and reverse processes are occuring at equal ratessuch that the macroscopic system appears to be static. It is symbolized by the double arrows in opposite directions of the same length to remind us that the forward and reverse (re)actions are proceeding at equal rates, resulting in a balanced system.

Second off, doing a high schoolers phsycis homework for him usually isnt a good thing. Though at least he isnt doing it on Sunday night. He could try googling around for these, its all basic physics that will be found in numerous places on the web. Motion in a plane is easy

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epgs does his own homework.
T or F

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F

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He is doing his own hw...Technically he is doing research. You guys just told him the answer....you should of helped him instead LOL

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Originally posted by Neo3Net
He is doing his own hw...Technically he is doing research. You guys just told him the answer....you should of helped him instead LOL
Ideally we should have said, remember the formula f=ma and things like that, but yeah, its a bit too late.

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if he's doing his homework ..well, he is !

it's one way of doing it, and a viable way

when I was studying economics I used to phone a well - known (in my country) economist from a left perspective, and then shamelessly made a few radio programmes about 'understanding our economic system' which went well with the listeners and also helped me with my assignments .. or homework if you want to call it that ..

I call it showing initiative

hope he got his work in time and scored well

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