Assignment 1

How many stars are in our solar system?

One - the Sun

What are the two most commonly found types of atoms in the universe?

Hydrogen and helium

Explain the difference between our solar system, our universe, and our galaxy.

Solar system: the Sun and the eight planets that surround it

Universe: everything that exists

Galaxy: the Milky Way, a collection of stars

Explain how the self-correcting aspect of the modern scientific process allows us to make progress, gaining a better and better understanding of our universe.

Scientists can send their hypotheses to other scientists around the world, who may determine its validity and gain better understanding of the universe

Why is there so much math in science?

Math is very specific and can make natural observations easier to understand; we can make accurate measurements within math

Why do astronomers prefer to create their models of the universe using equations rather than words?

Equations more easily predict specific numbers that can help determine the accuracy of theories; equations cannot be misunderstood like words can

The number 4.29 x 10^5 is in scientific notation. Write it in normal decimal notation.

429,000

The number 1.21 x 10^-4 is in scientific notation. Write it in normal decimal notation. \n

0\.000121

Write the number 2,370,000 in scientific notation.

2\.37 x 10^6

Write the number 0.000282 in scientific notation.

2\.82 x 10^-4

Find (2.32 × 10^6) × (3.41 × 10^4) (Please give your answer to this and the following questions in scientific notation. Also, notice that in this and the following questions, numbers are given to 3 significant figures, so be sure to round off your answers to 3 figures as well.)

7\.91 x 10^10

Find (8.23× 10^11) / (6.51× 10^9). Hint: Your answer should be between 100 and 500.

1\.26 x 10^2 or 126.4

Find 7.00^3/2. That's 7.00 to the power of 3/2, and 3/2 = 1.5. Hint: Your answer should be between 15 and 20.

18\.5

Suppose we discover an asteroid that is a distance of 4.23 × 10^9 km away. Convert this number to AU. Hint: Conversion factors are in Appendices D and E in the back of your textbook.

28\.3 AU

A planet is 4.22 × 10^9 km from the Sun. Using the speed of light (given in your book) calculate how long it takes for light from the Sun to reach this planet. Convert your answer to minutes.

8\.4 x 10^5 minutes

Suppose a space probe is so far away that its radio signals take 15.5 hours to reach us. Knowing that radio signals travel at the speed of light, calculate how far away this probe is in kilometers. Give your answer in scientific notation.

14,067 seconds = 234 minutes = 2.34 x 10^2 minutes