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The magnetic flux ($\Phi_B$) through a rotating coil in an AC generator at any time $t$ is given by:
From the NCERT text, 'the flux at any time t is $\Phi_B = BA \cos \theta = BA \cos \omega t$'.
What is the instantaneous value of the induced EMF ($\varepsilon$) in an AC generator with $N$ turns, area $A$, magnetic field $B$, and angular speed $\omega$?
The NCERT text states, 'Thus, the instantaneous value of the emf is $\varepsilon = NBA \omega \sin \omega t$ (6.19)'.
If the maximum value of the induced EMF in an AC generator is $\varepsilon_0$, how is it related to the parameters of the coil and magnetic field?
The NCERT text defines $\varepsilon_0$ as, 'where $NBA \omega$ is the maximum value of the emf... If we denote $NBA \omega$ as $\varepsilon_0$, then $\varepsilon = \varepsilon_0 \sin \omega t$ (6.20)'.
At what angle ($\theta$) between the area vector and the magnetic field does the induced EMF in an AC generator have its extremum (maximum or minimum) value?
The text states, 'Note from Fig. 6.14 that the emf has its extremum value when $\theta = 90^{\circ}$ or $\theta = 270^{\circ}$, as the change of flux is greatest at these points.'
Which component connected to the ends of the coil in an AC generator allows the transfer of induced current to an external circuit?
The NCERT text mentions, 'The ends of the coil are connected to an external circuit by means of slip rings and brushes.'
In the equation for instantaneous EMF, $\varepsilon = \varepsilon_0 \sin 2\pi nt$, what does '$n$' represent?
The NCERT text explains, 'Since $\omega = 2\pi n$, Eq (6.20) can be written as $\varepsilon = \varepsilon_0 \sin 2\pi n t$ (6.21) where $n$ is the frequency of revolution of the generator’s coil'.
The polarity of the EMF produced by an AC generator changes periodically. This is because:
The NCERT text states, 'Since the value of the sine function varies between +1 and –1, the sign, or polarity of the emf changes with time.'
Nicola Tesla is credited with the development of which significant aspect related to AC generation?
The NCERT text explicitly states, 'The Yugoslav inventor Nicola Tesla is credited with the development of the machine (AC generator).'
In an AC generator, the mechanical energy required to rotate the armature can be provided by different sources. Which type of generator uses water falling from a height?
The NCERT text states, 'In commercial generators, the mechanical energy required for rotation of the armature is provided by water falling from a height, for example, from dams. These are called hydro-electric generators.'
Alkanes exhibit which type of isomerism due to free rotation along C-C sigma bonds?
The NCERT summary states: 'Alkanes show conformational isomerism due to free rotation along the C–C sigma bonds. Out of staggered and the eclipsed conformations of ethane, staggered conformation is more stable as hydrogen atoms are farthest apart.'
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.