Diameter of milky way is 1.0 *10^5 light years

AI Thread Summary
The diameter of the Milky Way is approximately 100,000 light years, while the distance to the Andromeda galaxy is about 2 million light years. To create a scale model where the Milky Way and Andromeda are represented as dinner plates with a diameter of 25 cm, one must determine the corresponding distance between the two plates. A suggestion is made to convert light years into meters for consistency, as there are about 10^16 meters in a light year. Working in the same units simplifies the calculations and helps newcomers to physics better understand the concepts involved.
lilydaisy15
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hey guys, I'm new to physics .. and to be frank it seems scary. :-p
anyways i was wondering if anyone could help me with this:
The diameter of milky way is 1.0 *10^5 lightyears (ly). The distance to Andromeda is about 2.0 million ly. If a scale model represents the milky ways and andromeda galaxies as dinner plates 25 cm in diameter, determine the distance between the two plates.

thanks you guys!
 
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So, what do YOU think is needed here?
 
I'll give you a clue to start you off, there are about 10^16 metres per light year.
 
colinr said:
I'll give you a clue to start you off, there are about 10^16 metres per light year.

I don't see how that helps at all!

lilydaisy15: your model is making 100000 ly correspond to 25 cm.
what would 2 million= 2000000 ly correspond to?
 
well don't you need to know how many metres are in a light year before you can think about how many 25 cm are in 2 million light years
 
well ok, you don't, but it is better to work in the same units for stuff like this when you're new to the subject
 
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