Question

If we use 1 millimeter to represent 1 light-year, how large in diameter is the Milky Way Galaxy?

a.100 millimeters
b.100 kilometers
c.1 kilometer
d.100 meters
e.1 million millimeters

Answer 1

d.100 meters

Step-by-step explanation:

The diameter of the Milky Way Galaxy is approximately 100,000 light years.

Here we are using 1 millimiter (1 mm) to represent 1 light-year (1 ly). So, we can set the following proportion:

`1 mm : 1 ly = x : 100,000 ly`

and by finding x, we find the diameter of the Milky Way Galaxy in the scale used:

`x=((1mm )(100,000 ly))/(1 ly)=100,000 mm = 100 m`

so the correct answer is

d. 100 meters