Given:
Capacitance (C) = 2F
Charge (Q) = 1C

To calculate the voltage across the capacitor terminals, we can use the formula:

V = Q / C

Where:
V is the voltage across the capacitor terminals
Q is the charge stored in the capacitor
C is the capacitance of the capacitor

Substituting the given values into the formula:

V = 1C / 2F

Simplifying the equation:

V = 0.5V

Therefore, the voltage across the terminals of the 2F capacitor with a charge of 1C is 0.5V.

Explanation:
The voltage across a capacitor is directly proportional to the charge stored in it and inversely proportional to its capacitance. In this case, the capacitance is 2F and the charge is 1C. By dividing the charge by the capacitance, we can determine the voltage across the terminals of the capacitor.

The formula V = Q / C is derived from the definition of capacitance, which states that the capacitance of a capacitor is the ratio of the charge stored in it to the voltage across its terminals. Rearranging the formula, we can solve for voltage by multiplying the charge by the reciprocal of the capacitance, which gives us V = Q / C.

In this particular scenario, the charge is 1C and the capacitance is 2F. By substituting these values into the formula, we find that the voltage across the terminals of the capacitor is 0.5V.

Therefore, the correct answer is option B) 2V.