simple relativity question

[Sarahisme]

just checkin that my mind is working in the right way....

 

i would say passeenger B measures:

 

A: 39.2 m

B: 91.9 m

 

do peoples agree with me?

 

-Sarah

[wormholeman]

No, the two space ships

lengths are:

 

A:100 m long

B:36 m long

 

Trick question!

[Meir Achuz]

My calculator agrees wilth you, but I would give each answer to 2 sf to agree with the sf of the relative velocity.

[wormholeman]

Im sorry, It not a trick question!

[Sarahisme]

so who had the correcct answer then!?

[wormholeman]

lol..me!

[Sarahisme]

i am not sure your answer is correct.... does passenger is ship A see the length of ship B as contracted and so the real length of be would be greater than 36 m.....??

[losfomot]

just checkin that my mind is working in the right way....

 

i would say passeenger B measures:

 

A: 39.2 m

B: 91.9 m

 

do peoples agree with me?

 

-Sarah

 

 

Yes.. using the length contraction equation, those are the answers I got.

 

A= 39.2 m

B= 91.9 m

[Sarahisme]

then what is wormholeman on about?

[wormholeman]

ya, I can admit im wrong..

[wormholeman]

You see this is what I calculated.

I thought that 0.92c was 0.92 percent

of 100, so being that c is 186000 miles

per second. I divide 0.92 which I thought

became to be 92. Then dividing 92 by 186000

equaling 2021.73 miles per second. This

wasent what I thought right away mind you.

The reason I said (A): equals 100 and (b)

equals 36, cause I figured that it was

plainly spelled out. So, at 2021.73 miles per second

probobley would stretch the space ships a bit,

If thats what you mean.

 

How did you people get your answers?

[Sarahisme]

oh ok i see what you mean, we got our answers by as losfomot said

 

using the length contraction equation

[timo]

... we got our answers by as losfomot said

Which directly leads me to the point why I was a bit disappointed about this thread: Why didn´t YOU say how you derived your result? I mean: It´s ok if you ask for help on homework and it´s great that you already have some results and just want them checked. But for the future (or here, "I used length contraction" is quite a lose description of how you derived your numbers) it would be great if you´d add the steps that led you to your results.

Imho there are a lot of people in this forum who can tell you if your calculations are correct with just one look at your steps. But I´m not sure if all of them want to search for a pocket calculator just for a "your numbers are correct/incorrect" answer. At least, I don´t want to (and I wouldn´t even know where my calc is ).

You have to multiply one of the lengths by the length contraction factor and divide the other one by it. Dunno if your numbers are correct.

[wormholeman]

I used the calculator in my Windows operating system.

I think you have to calculate both lengths because

its says "relative". meaning: in relation to other. And

that would mean there moving at the same speed (92c),

and if they are at different lengths and if using the

"length contraction equation" (which I havent looked up

on how I could use it), will affect the question.

[Sarahisme]

Which directly leads me to the point why I was a bit disappointed about this thread: Why didn´t YOU say how you derived your result? I mean: It´s ok if you ask for help on homework and it´s great that you already have some results and just want them checked. But for the future (or here' date=' "I used length contraction" is quite a lose description of how you derived your numbers) it would be great if you´d add the steps that led you to your results.

Imho there are a lot of people in this forum who can tell you if your calculations are correct with just one look at your steps. But I´m not sure if all of them want to search for a pocket calculator just for a "your numbers are correct/incorrect" answer. At least, I don´t want to (and I wouldn´t even know where my calc is ).

You have to multiply one of the lengths by the length contraction factor and divide the other one by it. Dunno if your numbers are correct.[/quote']

 

 

fair enough, i see your point. i will try to do this in the future