A potentiometer wire AB of length L and resistance 12r is connected to a cell D with emf e and internal resistance 3r. Find length AJ wherein the galvanometer as shown in image shows no deflection.

Potential gradient can be expressed as the potential difference per unit length of wire.

Therefore, the potential gradient = (ε/12r + r) × (12r/L)]

= (ε/13r) × (12r/L)

= 12ε/13L

⇒ (12ε/13L )x = ε/2

⇒ x = \(\frac{13L}{24}\)


Related Questions

  1. Sensitivity of potentiometer can be increased by_______.
  2. What are the types of potentiometers?
  3. Which Metal Is Used In Potentiometer?
  4. Why Do We Prefer A Potentiometer With A Longer Bridge Wire?
  5. Why High Resistance Is Used In Potentiometer?
  6. Why Potentiometer Is Preferred Over Voltmeter?
  7. State the Working Principle of a Potentiometer.
  8. What is a null point in a potentiometer?
  9. What is the symbol for a potentiometer?
  10. What is balance point in potentiometer?
  11. How does a potentiometer measure EMF?
  12. Copper is not used as potentiometer wire because?
  13. What is a DC Potentiometer?
  14. What are the advantages of a potentiometer?
  15. How is potential gradient measured?
  16. What Is Balancing Length In Potentiometer?

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