Worksheet: Units of Astronomy: The Astronomical Unit (AU)

In this worksheet, we will practice converting between the astronomical length unit and meters and between the astronomical length unit and light-years.

Q1:

What is 3 . 1 × 1 0 km in AU? Give your answer to 2 significant figures.

Q2:

How many meters are there in 3.0 AU? Give your answer to 2 significant figures.

  • A 4 . 5 × 1 0 m
  • B 4 . 3 × 1 0 m
  • C 4 . 7 × 1 0 m
  • D 4 . 1 × 1 0 m
  • E 4 . 2 × 1 0 m

Q3:

Saturn orbits the Sun at a distance of about 9.6 AU. What is this distance in meters? Give your answer to 2 significant figures.

  • A 1 . 6 × 1 0 m
  • B 1 . 3 × 1 0 m
  • C 1 . 4 × 1 0 m
  • D 1 . 0 × 1 0 m
  • E 1 . 2 × 1 0 m

Q4:

What is 1 0 . 9 × 1 0 m in AU? Give your answer to 2 significant figures.

  • A 7.3 AU
  • B 9.4 AU
  • C 2.1 AU
  • D 6.8 AU
  • E 5.0 AU

Q5:

Mercury orbits the Sun at a distance of about 5 . 7 9 × 1 0 m. What is this distance in AU? Give your answer to 2 significant figures.

  • A 0.66 AU
  • B 0.57 AU
  • C 0.71 AU
  • D 0.39 AU
  • E 0.24 AU

Q6:

Pluto orbits the Sun at a distance of about 39 AU. How many hours does it take a beam of light from the Sun to travel this distance? Give your answer to 2 significant figures.

  • A 4.8 hours
  • B 7.0 hours
  • C 0.40 hours
  • D 3.5 hours
  • E 5.4 hours

Q7:

How many kilometers are there in 210 AU? Give your answer to 2 significant figures.

  • A 3 . 2 × 1 0 km
  • B 3 . 0 × 1 0 km
  • C 3 . 0 × 1 0 km
  • D 3 . 5 × 1 0 km
  • E 3 . 2 × 1 0 km

Q8:

Which distance is larger: 200,000 AU or 17 ly?

Q9:

Which of the following is the correct description of how the astronomical unit is defined?

  • AThe astronomical unit is a unit of length roughly equal to the distance between Pluto and the Sun.
  • BThe astronomical unit is a unit of length roughly equal to the distance between Jupiter and the Sun.
  • CThe astronomical unit is a unit of length roughly equal to the distance between Earth and the Sun.
  • DThe astronomical unit is a unit of length roughly equal to the distance between Venus and the Sun.
  • EThe astronomical unit is a unit of length roughly equal to the distance between Earth and the Moon.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.