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प्रश्न
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
Answer the following giving reason:
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
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उत्तर १
According to Ohm’s law, the relation for the potential is V = IR
Voltage (V) is directly proportional to the current (I).
R is the internal resistance of the source.
I = `V/R`
If V is low, then R must be very low, so that a high current can be drawn from the source.
उत्तर २
The maximum current that can be drawn from a source of emf E and internal resistance r is Imax = E/r. If E is low, r must be extremely small to allow a high value of Imax.
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