Chapter 7, Problem 7CCSR

To determine

To find: the distance between two stars.

Answer to Problem 7CCSR

The correct answer is C.

Explanation of Solution

Given information:

A light year is the distance light travels in one year. One light year is about $5.9\times {10}^{12}$ . If it takes light 3 months to travel from one start to another

Given options are,

1. $2\times {10}^3$ mi
2. $1.5\times {10}^4$ mi
3. $1.5\times {10}^{12}$ mi
4. $2\times {10}^{12}$ mi

Calculation:

The distance between two stars is equal to the distance covered by the light in 3 months.

The distance between one start to another can be calculated as follows

  $\begin{array}{c}\text{distance}=\text{distance}\text{covered}\text{by}\text{the}\text{light}\text{in}3\text{months}\\ \text{=}\frac{1}{4}\left(\text{distance}\text{covered}\text{by}\text{the}\text{light}\text{in}\text{one}\text{year}\right)\\ =\frac{1}{4}\left(\text{light}\text{year}\right)\\ =\frac{5.9\times {10}^{12}}{4}\text{mi}\\ \text{=1}\text{.5}\times {\text{10}}^{12}\text{mi}\end{array}$

The correct answer is C.