A potentiometer contains a wire of length 4m and resistance 10ohms (connected to EMF 3V). Find potential gradient of wire (1) 0.75 V/m (2) 2 V/m (3) 6 V/m (4) 10 V/m

A potentiometer can be defined as a three-terminal resistor with either rotating or sliding contact that develops an adjustable voltage divider. Now, as per the given question, we following can be said:

  • Potentiometer wire (L) = 4m
  • Resistance (R) = 10Ω
  • EMF of the cell = 3V

The potential across potentiometer wire can be estimated as:

Vp = 10 × I

Here, I = E/R

Thus, after replacing the values:

⇒ I = 3/10

⇒ I = 0.3 A

⇒ Vp = 10 × 0.3

⇒ Vp = 3V

Potential gradient can be expressed as the potential difference per unit length. The SI unit of the potential gradient can be defined by replacing the unit of potential difference or voltage and length.

Therefore, it can be represented as:

Potential gradient (k) = Vp/L

⇒ k = 3/4

⇒ Hence, k = 0.75 Vm-1


Related Questions

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

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