Three charges are placed at the vertices of an equilateral triangle of sides 'a'. The force experienced by the charge placed at the vertex A in a direction normal to BC is :
Correct answer: C. The net force is directed normal to BC
- A. The net force is zero
- B. The net force is directed along line BC
- C. The net force is directed normal to BC
- D. The net force is directed towards vertex C
Explanation
In an equilateral triangle, the symmetry of the charge arrangement results in forces that can be resolved into components. The horizontal components of the forces from the charges at B and C cancel each other due to symmetry. The vertical components add up, resulting in a net force that is perpendicular to BC. Thus, the force experienced by the charge at vertex A is normal to BC, which aligns with Option C. For the other options:Option A is incorrect because the forces do not cancel out completely.Option B is incorrect because the net force cannot lie along BC due to the symmetry of the setup.Option D is incorrect because the resultant force does not direct toward vertex C, as the symmetry leads to a perpendicular force relative to BC.
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