MedVision ad

The question with the synchronised clocks (1 Viewer)

telstrarobs

New Member
Joined
Jul 30, 2011
Messages
4
Gender
Male
HSC
N/A
I'm a bit unsure about this one, I was wondering what people thought the answer was?

Thanks :)
 

brent012

Webmaster
Webmaster
Joined
Feb 26, 2008
Messages
5,290
Gender
Male
HSC
2011
It was simultaneity, practically exactly the same as the light activated doors in a train example but they mixed things up a bit. By using synchronised clocks they were trying to trick some people into thinking time dilation but that is not the case as that requires one of the clocks to be in the same reference frame as the observer.
 

sakatahahaha

Member
Joined
Feb 3, 2011
Messages
73
Gender
Undisclosed
HSC
N/A
It was simultaneity, practically exactly the same as the light activated doors in a train example but they mixed things up a bit. By using synchronised clocks they were trying to trick some people into thinking time dilation but that is not the case as that requires one of the clocks to be in the same reference frame as the observer.
In my answer i referred to the simultaneity b/s i.e. events occurring in one frame of reference aren't always the same in another frame of reference ... I talked about time dilation aswell though.. moving clock moves slower than a stationary one i.e. on earth .. what was the answer suppose to be?
 

brent012

Webmaster
Webmaster
Joined
Feb 26, 2008
Messages
5,290
Gender
Male
HSC
2011
It was simultaneity because the question was referring to the two clocks on the space ship as observed from Earth. I admit though I did mention time dilation myself but it was at the very bottom, in brackets and i explained why it wouldnt happen in this example (did that incase i interpreted the question completely wrong and could get a few marks for demonstrating knowledge on time dilation haha).
 

NubMuncher

Member
Joined
Jan 10, 2011
Messages
129
Gender
Male
HSC
2011
In my answer i referred to the simultaneity b/s i.e. events occurring in one frame of reference aren't always the same in another frame of reference ... I talked about time dilation aswell though.. moving clock moves slower than a stationary one i.e. on earth .. what was the answer suppose to be?
Perhaps went one step too far with time dilation, the answer was simply to use the relativity of simultaneity and apply it to the diagramn, i.e. the external viewer sees the back clock activate first since c is a constant and the plane is travelling at a speed close to the speed of light. The regular b/s :)
 

sakatahahaha

Member
Joined
Feb 3, 2011
Messages
73
Gender
Undisclosed
HSC
N/A
Perhaps went one step too far with time dilation, the answer was simply to use the relativity of simultaneity and apply it to the diagramn, i.e. the external viewer sees the back clock activate first since c is a constant and the plane is travelling at a speed close to the speed of light. The regular b/s :)
Lol i even gave an example of it .. That's pretty much what i said though but explained through time dilation out of the 4 marks what am i expecting do you think ??
 
K

khorne

Guest
Lol i even gave an example of it .. That's pretty much what i said though but explained through time dilation out of the 4 marks what am i expecting do you think ??
It's easy to explain. As the ship travels right, and as the light is emitted, but before it hits the clock, the clock on the left has moved forward, reducing the distance. The clock on the right has moved forward, increasing the distance. v=d/t, so a larger distance means a larger time (v=c) so the clock on the left hits first.
 

fxjkhr

New Member
Joined
Nov 4, 2009
Messages
9
Gender
Male
HSC
2011
From the rest frame on the ship, the constant velocity of 0.95c means that the result of the investigation are the same as if they were performed in any inertial frame of reference. However, since the earth is in relative motion to the investigation, you have to explain the relativity of simultaneity and quote the time dilation/length contraction formulae (why else would they give an exact velocity?) and also state that since the light is observed activating the clocks at different times, they won't be synchronised
 
K

khorne

Guest
From the rest frame on the ship, the constant velocity of 0.95c means that the result of the investigation are the same as if they were performed in any inertial frame of reference. However, since the earth is in relative motion to the investigation, you have to explain the relativity of simultaneity and quote the time dilation/length contraction formulae (why else would they give an exact velocity?) and also state that since the light is observed activating the clocks at different times, they won't be synchronised
It has nothing to do with dilation. They gave you a fast speed, because this concept only works at fast rates.
 

Wentworth

Member
Joined
Oct 21, 2011
Messages
81
Gender
Male
HSC
2011
lol they even used photocells in the question to trick people, although I don't know what they were trying to suggest with it :/
 

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

Top