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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

A low voltage supply from which one needs high currents must have very low internal resistance. Why?

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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?

कारण सांगा
लघु उत्तर
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उत्तर

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.

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पाठ 3: Current Electricity - Exercise [पृष्ठ १२९]

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एनसीईआरटी Physics Part I and II [English] Class 12
पाठ 3 Current Electricity
Exercise | Q 3.18 (c) | पृष्ठ १२९

व्हिडिओ ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्‍न

Graph showing the variation of current versus voltage for a material Ga As is shown in the figure. Identify the region of
(i) negative resistance

(ii) where Ohm's law is obeyed.


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How should the two resistances of 2 ohms each be connected so as to produce an equivalent resistance of 1 ohm?


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An electric bulb draws 1.2 A current at 6.0 V. Find the resistance of filament of bulb while glowing.


A car bulb connected to a 12 volt battery draws 2 A current when glowing. What is the resistance of the filament of the bulb? Will the resistance be more same or less when the bulb is not glowing?


In an experiment of verification of Ohm’s law following observations are obtained.

Potential difference V (in volt)

0.5 1.0 1.5 2.0 2.5
current I (in ampere) 0.2 0.4 0.6 0.8 1.0

Draw a V-I graph and use this graph to find:

  1. the potential difference V when the current I is 0.5 A,
  2. the current I when the potential difference V is 0.75 V,
  3. the resistance in a circuit.

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(a) What is the least count of the voltmeter?

(b) What is the reading shown by the voltmeter ?

(c) If the voltmeter is connected across a resistor of 20 `Omega` how much current is flowing through the resistor?


  1. Name and state the law which relates the potential difference and current in a conductor.
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Ohm’s law states the relationship between power and voltage.


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Reason: V = IR is the equation which defines resistance.


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Which of the following describes the V-I relation for an Ohmic conductor?


What is the nature of the graph obtained when potential difference is plotted against current for an Ohmic conductor?


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