A potentiometer wire of length and resistance L and R respectively are connected in series with emf E0 and resistance R1. One unknown emf E is balanced at length of potentiometer wire. Find emf.

The schematic diagram of the given question is can be illustrated as:

EMF

EMF

Current that passes via the potentiometer wire is:

= \(I = \frac{E_0}{r\ +\ r_1}\)

The potential differ nce in the wire equals:

= \(V = Ir = \frac{E_0r}{r\ +\ r_1}\)

Along the potentiometer, the potential gradient is:

\(\therefore\) \(kl = \frac{E_0r}{r\ +\ r_1L}\)

Thus, the unknown emf equals: \(\frac{E_0r}{r\ +\ r_1L}\)


Related Questions

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

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