Question

Gravitational force of attraction “F” exists between two point masses A and B when a fixed distance separates them. After mass A is tripled and mass B is halved, the gravitational attraction between the two masses is
1/6 F
2/3 F
3/2 F
6 F

Answer 1

Answer:

the new gravitational force between the two masses is $\frac{3}{2}$ of the original force (third option in the provided list)

Explanation:

Recall the expression for gravitational force : $F_g=G\,\frac{m_A*\,m_B2}{d^2}$, where $m_A$ and $m_B$ are the point masses, d the distance between them, and G the universal gravitational constant.

I our problem, the distant between the particles stays unchanged, and we need to know what happens with the magnitude of the force as mass A is tripled, and mass B is halved.

Initial force expression: $F_i=G\,\frac{m_A\,m_B}{d^2}$

Final force expression: $F_f=G\,\frac{3*m_A\,m_B/2}{d^2}\\F_f=G\,\frac{m_A\,m_B\,*\,3/2}{d^2}\\F_f=G\,\frac{m_A\,m_B}{d^2}\,*\frac{3}{2} \\F_f=F_i\,*\frac{3}{2}$

Where we have recognized the expression for the initial force between the particles, and replaced it with $F_i$ to make the new relation obvious.

Therefore, the new gravitational force between the two masses is $\frac{3}{2}$ of the original force.

Answer 2

Answer:

3/2 F is the Answer