Question
Write the difference between alternating current and voltage.
✓
Answer
When a coil is rotated rapidly in a strong magnetic field, then there is continuous change in the flux linked with the coil due to which an emf is induced in the coil and induced current flows. Direction and magnitude of both emf and current changes with rotation of the coil and these types of voltage and current is known as alternating voltage and alternating current.
Instantaneous values of alternating voltage is given by the expressions
$E = E _0 \sin (\omega t+\phi)$
or $E = E _0 \cos (\omega t+\phi)$
Here E is instantaneous value, $E _0$ is peak value $=$ $NB \omega A$ and $(\omega t+\phi)$ is the phase.
In the same way, instantaneous values of alternating current is given by the expressions
$I=I_0 \sin (\omega t+\phi)$
or $I = I _0 \cos (\omega t +\phi)$
$I = instantaneous$ value, $I _0=$ peak value and its value is $\frac{ N \omega BA }{ R }$.
Where R is the resistance of the coil.
Instantaneous values of alternating voltage is given by the expressions
$E = E _0 \sin (\omega t+\phi)$
or $E = E _0 \cos (\omega t+\phi)$
Here E is instantaneous value, $E _0$ is peak value $=$ $NB \omega A$ and $(\omega t+\phi)$ is the phase.
In the same way, instantaneous values of alternating current is given by the expressions
$I=I_0 \sin (\omega t+\phi)$
or $I = I _0 \cos (\omega t +\phi)$
$I = instantaneous$ value, $I _0=$ peak value and its value is $\frac{ N \omega BA }{ R }$.
Where R is the resistance of the coil.
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