Use the ratio version of Kepler's third law and the orbital information of Mars to determine Earth's distance from the Sun. Mars's orbital period is 687 days, and Mars's distance from the Sun is [tex]2.279 \times 10^{11} \, \text{m}[/tex].

A. [tex]1.49 \times 10^{11} \, \text{m}[/tex]
B. [tex]1.49 \times 10^{33} \, \text{m}[/tex]
C. [tex]3.34 \times 10^{11} \, \text{m}[/tex]
D. [tex]3.34 \times 10^{33} \, \text{m}[/tex]



Answer :

To determine Earth's distance from the Sun using Mars's orbital information and Kepler's third law, follow these steps:

### Step-by-Step Solution:

1. Identify the given data:
- Mars's orbital period ([tex]\(T_{Mars}\)[/tex]) = 687 days
- Mars's distance from the Sun ([tex]\(R_{Mars}\)[/tex]) = [tex]\(2.279 \times 10^{11}\)[/tex] meters

2. Write Kepler's Third Law in ratio form:
Kepler's Third Law can be represented as:
[tex]\[ \left(\frac{T_{1}}{T_{2}}\right)^2 = \left(\frac{R_{1}}{R_{2}}\right)^3 \][/tex]
Where [tex]\(T_{1}\)[/tex] and [tex]\(R_{1}\)[/tex] are the orbital period and distance for Mars, and [tex]\(T_{2}\)[/tex] and [tex]\(R_{2}\)[/tex] are the orbital period and distance for Earth respectively.

3. Given [tex]\(T_{2}\)[/tex] (Earth's orbital period):
[tex]\(T_{Earth} = 365.25\)[/tex] days

4. Set up the ratio equation for Mars and Earth:
[tex]\[ \left(\frac{T_{Earth}}{T_{Mars}}\right)^2 = \left(\frac{R_{Earth}}{R_{Mars}}\right)^3 \][/tex]
Substituting in the known values:
[tex]\[ \left(\frac{365.25}{687}\right)^2 = \left(\frac{R_{Earth}}{2.279 \times 10^{11}}\right)^3 \][/tex]

5. Solve for [tex]\(R_{Earth}\)[/tex]:

First, compute the ratio of the periods squared:
[tex]\[ \left(\frac{365.25}{687}\right)^2 \][/tex]
Simplify this to get a numerical value:
[tex]\[ \left(\frac{365.25}{687}\right)^2 \approx 0.282 \][/tex]

Now set this equal to the cubed ratio of the distances:
[tex]\[ 0.282 = \left(\frac{R_{Earth}}{2.279 \times 10^{11}}\right)^3 \][/tex]

6. Isolate [tex]\(R_{Earth}\)[/tex] by taking the cube root of both sides:
[tex]\[ \left(0.282\right)^{1/3} = \frac{R_{Earth}}{2.279 \times 10^{11}} \][/tex]

Calculate the cube root of 0.282:
[tex]\[ \left(0.282\right)^{1/3} \approx 0.657 \][/tex]

So,
[tex]\[ 0.657 = \frac{R_{Earth}}{2.279 \times 10^{11}} \][/tex]

7. Solve for [tex]\(R_{Earth}\)[/tex]:
[tex]\[ R_{Earth} = 0.657 \times 2.279 \times 10^{11} \][/tex]

Compute the multiplication:
[tex]\[ R_{Earth} \approx 1.498 \times 10^{11} \, \text{meters} \][/tex]

### Conclusion:
The Earth's distance from the Sun is approximately [tex]\(1.495 \times 10^{11}\)[/tex] meters, which is closest to the value [tex]\(1.49 \times 10^{11} \)[/tex] meters among the given options. Therefore, the correct answer is:

[tex]\[1.49 \times 10^{11} \, \text{meters}\][/tex]

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