CONCEPT:
Electric Charge: It is a physical property of a matter that experiences a force when placed in an electromagnetic field.
- Electric charges create electric fields.
- Two types of charges are found – 1.) Positive charge. 2.) Negative charge
- Force experienced when charge placed in the electromagnetic field is \({{F}^{\to }}=q\times {{E}^{\to }}\) where q = charge of the body (in coulomb). \({{E}^{\to }}\) = intensity of the electric field.
- SI unit of charge is Coulomb and the symbol is C. One coulomb is equal to the charge on 6.241 x 1018 protons.
Inductor: It is a passive electric component that stores energy in the form of magnetic field lines. It is a simple loop of wire.
- The inductance of the inductor could be measured by equation L = Φ / I where ϕ is magnetic flux and I is a current flowing through it.
- SI unit of inductance is Henry.
- Energy stored in Inductor U = ½ (LI2).
Capacitor: It is a device consisting of two conducting "plates" separated by an insulating material (dielectric). It stores energy in the form of an electric field with the help of an electric charge.
- The capacitance of a capacitor is measured by equation C = q /Δ v where q is charge and ∆ V is a potential difference.
- SI Unit of capacitance is Farad.
- Energy stored in Capacitor U = ½ (CV2)
Resistance: It is a measure of how the device reduces the flow of electric current, basically it opposes the flow of charges.
- Further, it states the ratio of the applied voltage to electric current flows through it.
- R = V/I [R is resistance, V is the potential difference and I is electric current].
- Also, R = ρ × (L/A) [where ρ is specific resistance of the material, l is the length of conductor and A is the cross-sectional area of the conductor].
- The unit of resistance is volt/ampere or ohm (Ω).
- It does not store energy.
Transformer: It is an electrical device that converts A/C current from one voltage to another.
EXPLANATION:
- A capacitor stores energy in the form of electrical charges and fields.
- Here, Co = Capacitance, V = voltage, A = area of the plates, d = distance between them.
\(\Rightarrow {{C}_{o}}=\frac{{{Q}_{o}}}{V}=\frac{{{\epsilon }_{o}}A}{d}\)
Important Points
- Remember Electric field lines are stored in capacitor & magnetic field lines are stored in Inductor.
