The gravitational force between Pluto and Charon is [tex]\( 3.61 \times 10^{18} \, N \)[/tex]. Pluto has a mass of [tex]\( 1.3 \times 10^{22} \, kg \)[/tex], which is only slightly greater than Charon's mass of [tex]\( 1.6 \times 10^{21} \, kg \)[/tex].

How far apart are Pluto and Charon?

A. [tex]\( 2.0 \times 10^7 \, m \)[/tex]
B. [tex]\( 2.4 \times 10^{12} \, m \)[/tex]
C. [tex]\( 3.8 \times 10^{14} \, m \)[/tex]
D. [tex]\( 5.8 \times 10^{24} \, m \)[/tex]



Answer :

Let's determine the distance between Pluto and Charon, given the provided values:

1. Step 1: Given Data
- Gravitational force ([tex]\( F \)[/tex]) between Pluto and Charon: [tex]\( 3.61 \times 10^{18} \, \text{N} \)[/tex]
- Mass of Pluto ([tex]\( m_1 \)[/tex]): [tex]\( 1.3 \times 10^{22} \, \text{kg} \)[/tex]
- Mass of Charon ([tex]\( m_2 \)[/tex]): [tex]\( 1.6 \times 10^{21} \, \text{kg} \)[/tex]
- Gravitational constant ([tex]\( G \)[/tex]): [tex]\( 6.67430 \times 10^{-11} \, \text{m}^3 \text{kg}^{-1} \text{s}^{-2} \)[/tex]

2. Step 2: Formula for Gravitational Force
The gravitational force formula is given by:
[tex]\[ F = G \frac{m_1 \cdot m_2}{r^2} \][/tex]
where [tex]\( r \)[/tex] is the distance between the centers of the two objects.

3. Step 3: Solving for [tex]\( r^2 \)[/tex]
Rearrange the above formula to solve for [tex]\( r^2 \)[/tex]:
[tex]\[ r^2 = G \frac{m_1 \cdot m_2}{F} \][/tex]

4. Step 4: Substitute the Values
Substitute the given values into the rearranged formula:
[tex]\[ r^2 = \frac{(6.67430 \times 10^{-11} \, \text{m}^3 \text{kg}^{-1} \text{s}^{-2}) \times (1.3 \times 10^{22} \, \text{kg}) \times (1.6 \times 10^{21} \, \text{kg})}{3.61 \times 10^{18} \, \text{N}} \][/tex]

5. Step 5: Compute [tex]\( r^2 \)[/tex]
After performing the computation:
[tex]\[ r^2 = 384558005540166.2 \, \text{m}^2 \][/tex]

6. Step 6: Compute [tex]\( r \)[/tex]
Take the square root of [tex]\( r^2 \)[/tex] to get [tex]\( r \)[/tex]:
[tex]\[ r = \sqrt{384558005540166.2} \approx 19610150.574132934 \, \text{m} \][/tex]

7. Step 7: Closest Matching Option
Consider the options given:
- [tex]\( 2.0 \times 10^7 \, \text{m} \)[/tex]
- [tex]\( 2.4 \times 10^{12} \, \text{m} \)[/tex]
- [tex]\( 3.8 \times 10^{14} \, \text{m} \)[/tex]
- [tex]\( 5.8 \times 10^{24} \, \text{m} \)[/tex]

The closest value to [tex]\( 19610150.574132934 \, \text{m} \)[/tex] (which is approximately [tex]\( 2.0 \times 10^7 \, \text{m} \)[/tex]) is [tex]\( 2.0 \times 10^7 \, \text{m} \)[/tex].

So, the distance between Pluto and Charon is closest to:
[tex]\[ \boxed{2.0 \times 10^7 \, \text{m}} \][/tex]