हिंदी

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. - Physics

Advertisements
Advertisements

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
Advertisements

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` 
shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Current Electricity - EXERCISE - 8(B) [पृष्ठ २००]

APPEARS IN

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

संबंधित प्रश्न

What happens to the resistivity of semiconductor with the increase of temperature?


Explain why the p.d across the terminals of a cell is more in an open circuit and reduced in a closed circuit. 


What is the colour code for the insulation on the earth wire?


Four cells, each of e.m.f. 1.5 V and internal resistance 2.0 ohms are connected in parallel. The battery of cells is connected to an external resistance of 2.5 ohms. Calculate:

(i) The total resistance of the circuit.
(ii) The current flowing in the external circuit.
(iii) The drop in potential across-the terminals of the cells.


Four cells each of e.m.f. 2V and internal resistance 0.1 Ω are connected in series to an ammeter of negligible resistance, a 1.6 Ω resistor and an unknown resistor R1. The current in the circuit is 2A. Draw a labelled diagram and calculate:

(i) Total resistance of the circuit,
(ii) Total e.m.f.
(iii) The value of R1 and
(iv) The p.d. across R1.


A cell supplies a current of 0.6 A through a 2Ω coil and a current of 0.3 A through on 8Ω coil. Calculate the e.m.f and internal resistance of the cell.


(a) Calculate the total resistance across AB.

(b) If a cell of e.m.f 2.4 V with negligible internal resistance is connected across AB then calculate the current drawn from the cell.


Study the diagram:

  1. Calculate the total resistance of the circuit.
  2. Calculate the current drawn from the cell.
  3. State whether the current through 10 Ω resistor is greater than, less than or equal to the current through the 12 Ω resistor.

Explain the meaning of the term internal resistance of a cell.


A battery of e.m.f. 6.0 V supplies current through a circuit in which the resistance can be changed. A high resistance voltmeter is connected across the battery. When the current is 3 A, the voltmeter reads 5.4 V. Find the internal resistance of the battery.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×