# The Naked Scientists Forum

### Author Topic: Could rails appear parallel in the distance?  (Read 1715 times)

#### Roger Wenner

• Guest
##### Could rails appear parallel in the distance?
« on: 14/12/2010 15:30:03 »
Roger Wenner  asked the Naked Scientists:

As you stand looking down a straight flat railway track, the rails appear to get closer together the farther away they are.

If the distance between the rails were slightly increased, in proportion to the distance, would they then appear to be parallel or further apart ?

What do you think?
« Last Edit: 14/12/2010 15:30:03 by _system »

#### SteveFish

• Guest
##### Could rails appear parallel in the distance?
« Reply #1 on: 14/12/2010 16:07:14 »
Roger, you could play around with this yourself with two long strings tied to something. If you were to adjust the string angles to each other so they appeared to be parallel they would still look wrong because appearing closer together with distance is a visual cue for distance. One can get more insight by understanding how perspective drawing works. If you draw two converging lines on a piece of paper, they will look like they are receding. If you draw two parallel lines on the paper they will look like they are vertical.

#### Bill S

• Neilep Level Member
• Posts: 1802
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##### Could rails appear parallel in the distance?
« Reply #2 on: 14/12/2010 17:42:50 »
Stay off any train that runs on Roger's tracks.

#### SteveFish

• Guest
##### Could rails appear parallel in the distance?
« Reply #3 on: 14/12/2010 18:20:43 »
Don't worry, I have a rubber train.

#### Bill S

• Neilep Level Member
• Posts: 1802
• Thanked: 11 times
##### Could rails appear parallel in the distance?
« Reply #4 on: 14/12/2010 18:53:16 »
Not just a stretch of the imagination?

#### Geezer

• Neilep Level Member
• Posts: 8328
• "Vive la résistance!"
##### Could rails appear parallel in the distance?
« Reply #5 on: 14/12/2010 19:03:59 »
Don't worry, I have a rubber train.

Do you entertain the passengers with music from an elastic band?

#### The Naked Scientists Forum

##### Could rails appear parallel in the distance?
« Reply #5 on: 14/12/2010 19:03:59 »