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Which one of the following is the correct dimensional formula for the capacitance in F ? M, L, T and C stand for unit of mass, length, time and charge,
The dimensional formula for capacitance in farads (F) can be derived using the definition of capacitance. Capacitance $$C$$ is given by the formula:
$$ C = \frac{Q}{V} $$
where $$Q$$ is the charge and $$V$$ is the potential difference.
Charge $$Q$$ has the dimension $$[C]$$, so:
$$ [Q] = [C] $$
Potential difference $$V$$ is defined as work done per unit charge:
$$ V = \frac{W}{Q} $$
where $$W$$ is work done. Work done $$W$$ is force multiplied by displacement:
$$ W = F \cdot d $$
Force $$F$$ is mass times acceleration:
$$ F = m \cdot a $$
Acceleration $$a$$ has dimension $$[LT^{-2}]$$, so force $$F$$ has dimension:
$$ [F] = [M] \cdot [LT^{-2}] = [MLT^{-2}] $$
Displacement $$d$$ has dimension $$[L]$$, so work done $$W$$ has dimension:
$$ [W] = [F] \cdot [d] = [MLT^{-2}] \cdot [L] = [ML^2T^{-2}] $$
Therefore, potential difference $$V$$ has dimension:
$$ [V] = \frac{[W]}{[Q]} = \frac{[ML^2T^{-2}]}{[C]} = [ML^2T^{-2}C^{-1}] $$
Now, capacitance $$C$$ is:
$$ [C] = \frac{[Q]}{[V]} = \frac{[C]}{[ML^2T^{-2}C^{-1}]} $$
Simplifying the expression:
$$ [C] = [C] \times \frac{1}{[ML^2T^{-2}C^{-1}]} = [C] \times [M^{-1}L^{-2}T^{2}C] = [C^{1} \cdot C^{1}] \times [M^{-1}L^{-2}T^{2}] = [C^{2}M^{-1}L^{-2}T^{2}] $$
Thus, the dimensional formula for capacitance is $$[C^{2}M^{-1}L^{-2}T^{2}]$$.
Comparing with the options:
Option A matches the derived dimensional formula.
Therefore, the correct answer is A.
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