Skip to content
Solved Assignments

Applications of Newton's Laws and Astronomical Units in Understanding Motion and Distance

An application of Newton's laws and astronomical units to understand motion and distance.

Preview 2 of 3 pages

See the first 2 pages exactly as they appear in the document.

  1. Page 1
    Read page 1 as text

    1 Applications of Newton's Laws and Astronomical Units in Understanding Motion and Distance Explain how a light - year is a unit of distance. Be sure to include the definition of a light - year in your explanation . Answer: - Light year is a unit used in astronomical calculations and is equivalent to the distance that light travels in one year which is close to 9.4607*10^12 km ( C. W. Allen (1973)) ( approximately). The requirement of using light year in astronomical calculations are required since there the usage of well known distance measuring unit like kilometer will not work well as the it is too small to be of practical use considering the distance to the next closest galaxy that is the Andromeda Galaxy is 21 quintillion km. That’s numerically 21,000,000,000,000,000,000 km - this is truly a large number to remember and write and hard to interpret quickly so astronomers have started the usage of light year as a unit for measuring distance. This in our solar system often referred to as the Astronomical Unit ( AU). The AU is used to define the average distance between the Sun and the Earth. The distance approximately becomes equal to 150 million km ( Astronomical Constants page K6 ) . As part of comparison, it can be said that the Mercury is about 1/3 rd of an AU from the Sun. Although, AU is quite big as a unit to measure astronomical distance but not so big when we consider other objects lying outside of our solar system. In those cases parsec is used which is equal to 3.3 light years. References http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html http://marshallbrain.com/science/lightyear.htm Astronomical Constants page K6 of the Astronomical Almanac .

  2. Page 2

1 more page in the full document

Unlock it once and it stays in your library, ready to chat with or turn into flashcards.

Unlock the full document

More Physics study materials

See all

Study this document with CramX

Once it is in your library, every tool can work from it.