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A cell of e.m.f ε and internal resistance r is used to send current to an external resistance R. Write expressions for a. the total resistance of circuit. b. the current drawn from the cell.

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प्रश्न

A cell of e.m.f ε and internal resistance r is used to send current to an external resistance R. Write expressions for

  1. the total resistance of circuit.
  2. the current drawn from the cell.
  3. the p.d. across the cell.
  4. voltage drop inside the cell. 
संख्यात्मक
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उत्तर

  1. Total resistance = R + r
  2. Current I = `"potential"/"Resistance"`
    = `ε/("R" + r)`
  3. p.d. across the cell : `(ε/("R"+r)) xx "R"`
  4. voltage drop inside the cell = I × Resistance
    =`ε/(("R"+r))xxr` 
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अध्याय 8: Current Electricity - EXERCISE - 8(B) [पृष्ठ २००]

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सेलिना Concise Physics [English] Class 10 ICSE
अध्याय 8 Current Electricity
EXERCISE - 8(B) | Q 4. | पृष्ठ २००

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