The distance across Earth is measured in a different scale than the distance across the Milky Way. Which term is commonly used when measuring the distance across the Milky Way?(1 point)
Responses
year
year
miles
miles
light-years
light-years
space kilometers
light-years
Solar System Online Practice
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Question
Use this paragraph: A scale model of the solar system shows a dot placed at the center to represent the sun. Mercury is approximately 60,000,000 km from the sun and is placed on the model at a distance of 10 cm from the dot. Likewise, the Earth is approximately 150,000,000 km from the sun.
At which distance from the dot should Earth be placed in the model?
(1 point)
Responses
25 cm
25 cm
21 cm
21 cm
900 cm
4CM
21 cm
WRONG
I apologize for the incorrect response. Let's calculate the distance at which Earth should be placed on the scale model.
If Mercury is placed at a distance of 10 cm on the model and is approximately 60,000,000 km from the sun, we can find the scale factor by dividing the distance on the model by the actual distance.
Scale factor = Distance on model / Actual distance = 10 cm / 60,000,000 km
Now, let's find the distance at which Earth should be placed on the model.
Distance on model = Scale factor * Actual distance
= (10 cm / 60,000,000 km) * 150,000,000 km
Distance on model = 25 cm
Therefore, Earth should be placed at a distance of 25 cm from the dot on the model.
The term commonly used when measuring the distance across the Milky Way is "light-years."
The term commonly used when measuring the distance across the Milky Way is "light-years".
To understand why light-years are used, we need to first understand what a light-year is. A light-year is the distance that light travels in one Earth year, which is approximately 9.46 trillion kilometers or 5.88 trillion miles.
Measuring such vast distances like the size of the Milky Way in regular kilometers or miles would be impractical and inconvenient due to the extreme distances involved. The Milky Way is a spiral galaxy with a diameter of about 100,000 light-years. So when we say the distance across the Milky Way is measured in light-years, it means we are considering the time it takes for light to travel across that distance.
Therefore, the term "light-years" is used as a unit of measurement when referring to the distance across the Milky Way.