• Best of luck to the class of 2024 for their HSC exams. You got this!
    Let us know your thoughts on the HSC exams here
  • YOU can help the next generation of students in the community!
    Share your trial papers and notes on our Notes & Resources page
MedVision ad

Time Dilation EXPLAINED, read this before you argue in the other thread (1 Viewer)

Bannanafish

Member
Joined
Sep 25, 2003
Messages
153
Gender
Male
HSC
2003
EXPLANATION #1

Acceleration of the spaceship, taking time for the astronaut to "see" the clock on earth, and any other "complications" are all irrelivant. This is a THOUGHT experiment, hence ignoring all these factors. Hell, if it weren't i'd argue how the hell could the astronaut see a clock so far away?? Also in Einstein's THOUGHT experiment, he never said anytihng about acceleration (which is obviously needed for his trains to travel so fast).

So since we can ignore all these things, think of the spaceship as a train.
Train is travelling at 0.8c
Goes past an observer
Observer looks in the window of the train and the clock inside is running slow (i.e. for every second on his watch, the clock is only going a fraction of a second)
The passenger on the train looks at the observer's watch and sees it as going slow (i.e. for every second on his clock, the watch is only going a fraction of a second)
If the observer sees something to take 10 seconds according to his watch, then he sees the clock inside the train go 6 second.
If the passenger sees something to take 10 seconds according to his clock, then he sees the watch on the observer to go 6 seconds.
Now if 10 seconds was 10 years, the PASSENGER'S clock READS 10 hours. THIS IS WHAT THE QUESTION GAVE YOU.
Now the PASSENGER looks at the OBSERVERS watch. THIS IS THE PERSPECTIVE THE QUESTION ASKED.
Therefore the OBSERVERS watch would say 6 years have passed.

-------------------

EXPLANATION #2

the question now becomes, train though experiment or twins paradox

if for trains:
spaceship measures 10 years (given)
spaceship views earth as 6 years
earth measures 10 years
earth views spaceship as 6 years
since both perspectives are as valid as the other, earth is 6 years with the perspective of the spaceship (that's the perspective the question asked)
therefore B is correct

for twins paradox:
spaceship measures 10 years (given)
spaceship views earth as 6 years
earth measures 10 years
earth views spaceship as 6 years
since in twins paradox, spaceship comes back, earths perspective is taken preference, therefore the people on earth are older than the people in the spaceshit, BUT it's 10years older for earth people, 6 years older for space people
therefoe C is correct

------------------

Therefoe D is definately wrong, even arguing from your perspective, you are saying C is correct
 

Skywalker

Member
Joined
Aug 10, 2003
Messages
337
Gender
Undisclosed
HSC
N/A
Um.

Why do you bother?

Physics is over and done with and these threads are ultimately pointless. Trying to convince other people your answer was correct won't change your answer nor the BOS answers. Some of you should take a break from these forums, seriously.
 

Bannanafish

Member
Joined
Sep 25, 2003
Messages
153
Gender
Male
HSC
2003
probably cause i'm bored of studying for biology :p comparitively physics is so interesting
 
N

ND

Guest
Originally posted by Bannanafish
probably cause i'm bored of studying for biology :p comparitively physics is so interesting
You should've done chem. :p
 

bails

Member
Joined
Aug 24, 2003
Messages
155
Location
Newy
Righton not that i really care at all coz its one mark but im so confused b4 u said it was b, and now ur sayin it was B & C

Originally posted by Bannanafish
it was B
go check
Originally posted by Bannanafish
therefore B is correct...therefoe C is correct

Therefoe D is definately wrong, even arguing from your perspective, you are saying C is correct
Yeah im really confused, is there any official answer yet?
 

juber

jhv,m
Joined
Jun 20, 2003
Messages
86
Location
jh
Gender
Undisclosed
HSC
N/A
Ok, I just got word from a friends physics tutor who is part of the marking center, and they dont start trying to figure out answers n stuff til monday, but anyway, this tutor said that there was a lot of debate about this question by a few head markers, and that there was a very likely chance that they will accept both.
 

Bannanafish

Member
Joined
Sep 25, 2003
Messages
153
Gender
Male
HSC
2003
hahahah sounds good, so i'll get a mark for d? even though it's b? oh no shhh... it's d!!!
 

CloudStrife

Member
Joined
Nov 1, 2003
Messages
146
Location
Sydney
Gender
Male
HSC
2003
heheh, as juber suggested, this maybe one of those questions that they may give 2 answers for because the wording wasn't too clear to provide a precise answer...
 

juber

jhv,m
Joined
Jun 20, 2003
Messages
86
Location
jh
Gender
Undisclosed
HSC
N/A
see the thing is that the question was written with B being the intended answer...

So like I think that B is the correct answer for the fact that you needed to view the frame of reference as the spaceship and not earth.

I dont think people can claim otherwise (unless you get into all sorts of other stuff which is just far beyond the course which makes it irrelevant - as someone said, you may has well claim that you couldn't see the clock from that far away)

But man, I hope they take D as well cos i put D!
 

Dave_B

New Member
Joined
Nov 3, 2003
Messages
10
the question specifically asks to view the earth's clock from the spaceship.

Time diliates in both frames (which is the paradox thing, no need to go into it) so the answer has to be less than 10 years. This is only from the perspective of the ship tho, not the perspective of a 3rd party on earth
 

sunken eyes

Member
Joined
Sep 5, 2003
Messages
91
Gender
Male
HSC
2003
hang on a sec. we learnt the time dilation formula. we have 10 yrs, and 0.8c spped. just plug it in and u get 6 yrs right? how is there a debate about it. 6 yrs is the answer we get from the formula right? so why the blue?
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top