College

Objects with masses of 215 kg and 579 kg are separated by 0.493 m. A 64 kg mass is placed midway between them.

Find the magnitude of the net gravitational force exerted by the two larger masses on the 64 kg mass. The value of the universal gravitational constant is [tex]6.672 \times 10^{-11} \, \text{N} \cdot \text{m}^2 / \text{kg}^2[/tex].

Answer in units of N.

Answer :

Sure! Let's work through the solution step by step to find the net gravitational force exerted on a 64 kg mass placed midway between two larger masses.

Step 1: Understand the Problem and Given Information
- We have three masses: 215 kg, 579 kg, and 64 kg.
- The 64 kg mass is placed exactly midway between the 215 kg and 579 kg masses.
- The distance between the 215 kg and 579 kg masses is 0.493 meters.
- We are given the universal gravitational constant, [tex]\( G = 6.672 \times 10^{-11} \, \text{N} \cdot \text{m}^2/\text{kg}^2 \)[/tex].

Step 2: Determine the Distances
- Since the 64 kg mass is exactly in the middle, it is 0.493 m / 2 = 0.2465 m away from each of the larger masses.

Step 3: Calculate the Gravitational Force from the 215 kg Mass
The formula for gravitational force is:
[tex]\[
F = \frac{G \cdot m_1 \cdot m_2}{r^2}
\][/tex]
For the 215 kg mass:
- [tex]\( m_1 = 215 \, \text{kg} \)[/tex]
- [tex]\( m_2 = 64 \, \text{kg} \)[/tex]
- [tex]\( r = 0.2465 \, \text{m} \)[/tex]

Substituting the values:
[tex]\[
F_1 = \frac{6.672 \times 10^{-11} \cdot 215 \cdot 64}{0.2465^2}
\][/tex]
[tex]\[
F_1 \approx 1.5109 \times 10^{-5} \, \text{N}
\][/tex]

Step 4: Calculate the Gravitational Force from the 579 kg Mass
For the 579 kg mass:
- [tex]\( m_1 = 579 \, \text{kg} \)[/tex]
- [tex]\( m_2 = 64 \, \text{kg} \)[/tex]
- [tex]\( r = 0.2465 \, \text{m} \)[/tex]

Substituting the values:
[tex]\[
F_2 = \frac{6.672 \times 10^{-11} \cdot 579 \cdot 64}{0.2465^2}
\][/tex]
[tex]\[
F_2 \approx 4.0689 \times 10^{-5} \, \text{N}
\][/tex]

Step 5: Determine the Net Gravitational Force
- The forces [tex]\( F_1 \)[/tex] and [tex]\( F_2 \)[/tex] are in opposite directions because one mass is on one side of the 64 kg mass and the other is on the opposite side.
- The net gravitational force is the difference between these two forces because [tex]\( F_2 > F_1 \)[/tex].

Calculate the net force:
[tex]\[
\text{Net Force} = F_2 - F_1
\][/tex]
[tex]\[
\text{Net Force} = 4.0689 \times 10^{-5} - 1.5109 \times 10^{-5}
\][/tex]
[tex]\[
\text{Net Force} \approx 2.5580 \times 10^{-5} \, \text{N}
\][/tex]

So, the magnitude of the net gravitational force exerted on the 64 kg mass is approximately [tex]\( 2.5580 \times 10^{-5} \, \text{N} \)[/tex].