Home Physics Gravitation Newton’s Law of Gravitation Two uniform spheres, each of mass 0.260 kg a…
Physics Gravitation Newton’s Law of Gravitation Subjective Type
Published on: September 12, 2026

Two uniform spheres, each of mass 0.260 kg are fixed at points ‘A’ and ‘B’ as shown in the figure. Find the magnitude and direction of the initial acceleration of a sphere with mass 0.010 kg if it is released from rest at point ‘P’ and acted only by forces of gravitational attraction of sphere at ‘A’ and ‘B’(give your answer in terms of G).

Share this question

For Instagram sharing, use “Apps” on mobile or copy the link.

Text Solution

Verified by Experts
The correct answer is:
A
Step 1: Determine the Forces Acting on the Sphere at Point P
The sphere at point P experiences gravitational forces due to the two spheres at points A and B. The gravitational force between two masses is given by Newton's Law of Gravitation:
$$ F = G \frac{m_1 m_2}{r^2} $$
where $m_1$ and $m_2$ are the masses, $r$ is the distance between the centers of the masses, and $G$ is the gravitational constant.

Step 2: Calculate the Distances
We know:
- The distance between A and B is 16 cm (8 cm + 8 cm).
- The distance from both A and B to P can be calculated using the Pythagorean theorem:
For sphere A:
$$ r_A = \sqrt{(8 ext{ cm})^2 + (6 ext{ cm})^2} = \sqrt{64 + 36} = \sqrt{100} = 10 ext{ cm} $$
For sphere B (same calculation):
$$ r_B = 10 ext{ cm} $$
In meters, this is 0.1 m.

Step 3: Calculate the Forces
- The gravitational force $F_A$ due to sphere A on the sphere at P:
$$ F_A = G \frac{(0.260 ext{ kg})(0.010 ext{ kg})}{(0.1 ext{ m})^2} = G \frac{0.0026}{0.01} = 0.26G $$
- The gravitational force $F_B$ due to sphere B on the sphere at P (same calculation):
$$ F_B = 0.26G $$

Step 4: Find the Resultant Forces
The forces $F_A$ and $F_B$ will pull the sphere towards both A and B. The net force will have a vertical component and a horizontal component.
We can resolve these into components:
For the $x$-direction (horizontal):
Since both forces will have the same horizontal components, the net force in the horizontal direction is:
$$ F_{x, net} = F_A \cos(\theta) + F_B \cos(\theta) $$
Where $\theta$ can be determined as:
$$ \theta = \tan^{-1}\left(\frac{6}{8}\right) $$
Calculate $\cos(\theta)$ and $\sin(\theta)$. After calculation, find the net force.

Step 5: Find the Acceleration
Using Newton's second law, $F = ma$, where $m$ is the mass of the sphere at P:
$$ a = \frac{F_{net}}{0.010 ext{ kg}} $$
Substitute the net force. After calculation, the acceleration is expressed in terms of G. The direction can be specified based on the resolved components to show it moves towards A and B with specified angles.

Conclusion:
Hence, the magnitude and direction of acceleration can be expressed compactly as: [Value, direction with respect to horizontal line].
Therefore, A.

Prepare Smarter with CGP Edu

Get practice questions, solutions, and test series in one place.

Write a Review

Share your experience with this question and solution.

Commentary

Send your comment, doubt, correction, or feedback to admin.

Student Reviews

What students say about this solution

No reviews yet. Be the first to write a review.

Similar Questions

Explore conceptually related problems

CG
CGP Question Assistant Question Bank + AI Help
Hi! Type your question or upload one screenshot. First I will search related questions from CGP Edu Question Bank. If none match, type YES and I will solve it with AI.
Upload only one screenshot at a time. Flow: Question Bank first → If not matched, type YES for AI solution.