Recall Coulomb's Law, which states that the electrostatic force (F) between two charges is inversely proportional to the square of the distance (r) between them: F (1)/(r2).

Here are the solutions to the multiple-choice questions:

1. If distance between two charges is doubled, the Coulomb force becomes:

Step 1: Recall Coulomb's Law, which states that the electrostatic force ($F$) between two charges is inversely proportional to the square of the distance ($r$) between them: $F \propto \frac{1}{r^2}$.

Step 2: If the distance is doubled ($r' = 2r$), the new force ($F'$) will be:

$$F' \propto \frac{1}{(2r)^2} = \frac{1}{4r^2} = \frac{1}{4} F$$

The force becomes one-fourth of the original force.
The correct option is (B) One-fourth.

2. The dimensional formula of electric potential is:

Step 1: Electric potential ($V$) is defined as work done ($W$) per unit charge ($q$): $V = \frac{W}{q}$.

Step 2: The dimensions of work (energy) are $[ML^2T^{-2}]$.

Step 3: The dimensions of charge are $[AT]$ (current $\times$ time).

Step 4: Substitute these dimensions into the formula for electric potential:

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