JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The dimensional formula of \(\dfrac{1}{2}\epsilon_0 E^2\) (\(\epsilon_0\) = permittivity of vacuum and \(E\) = electric field) is \(M^a L^b T^c\). The value of \(2a - b + c = \) _______.
- A \(0\)
- B \(1\)
- C \(-1\)
- D \(2\)
Answer & Solution
Correct Answer
(B) \(1\)
Step-by-step Solution
Detailed explanation
The quantity \(\dfrac{1}{2}\epsilon_0 E^2\) represents the energy density of an electric field. Energy density is defined as energy per unit volume. Dimensional formula of energy is \([M L^2 T^{-2}]\). Dimensional formula of volume is \([L^3]\). Dimensional formula of energy…
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