Q64 / 90 · JEE Main 2023 (13 Apr Shift 2) · Physics

A $10 μ C$ charge is divided into two parts and placed at $1 cm$ distance so that the repulsive force between them is maximum. The charges of the two parts are:

A
$7 μ C, 3 μ C$
B
$8 μ C, 2 μ C$
Correct answer
C
$5 μ C, 5 μ C$
D
$9 μ C, 1 μ C$

Solution

Let the charges be $x μC, (q - x) μC$ , where $q = 10 μC$
The force between them is
$F = \frac{K x (q - x)}{r^{2}}$ .
For the force to be maximum,
$\frac{d F}{d x} = 0 \Rightarrow \frac{d F}{d x} = \frac{K (q - 2 x)}{r^{2}} = 0 \Rightarrow x = \frac{q}{2} = 5 μC$

Hence, the correct answer is option: 'C'.

Relevant Questions

Two point charges and are placed at points and respectively. Force on charge is ________ N.08 Apr, 2026 (E)Electric Charge and Coulomb's law
A point charge is located at a distance 2 cm from one end of a thin insulating wire of length 10 cm having a charge , distributed uniformly 24 Jan, 2026 (E)Electric Charge and Coulomb's law
Two metal spheres of radius and have same surface charge density . If they are brought in contact and then separated, the surface charge den08 Apr, 2025 (E)Electric Charge and Coulomb's law
A small bob of mass 100 mg and charge is connected to an insulating string of length 1 m. It is brought near to an infinitely long nonconduc02 Apr, 2025 (M)Electric Charge and Coulomb's law
A small uncharged conducting sphere is placed in contact with an identical sphere but having charge and then removed to a distance such that24 Jan, 2025 (E)Electric Charge and Coulomb's law
A positive ion and a negative ion has charges and , and masses and respectively. At an instant, the ions are separated by a certain distance23 Jan, 2025 (M)Electric Charge and Coulomb's law

A 10 μC charge is divided into two parts and placed at 1 cm distance so that the repulsive force between them is maximum. The charges of the two parts are:

Solution

Relevant Questions

A $10 μ C$ charge is divided into two parts and placed at $1 cm$ distance so that the repulsive force between them is maximum. The charges of the two parts are: