Question

Thermoelectric cooler works on the principle of

• A. Hall effect
• B. Seebeck effect
• C. Piezoelectric effect
• D. Peltier effect

Hint:

- Temperature difference $\rightarrow$ Voltage: Seebeck Effect (Sensors Thermocouples).
- Voltage Current $\rightarrow$ Temperature difference: Peltier Effect (Cooling Heating).

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
This is a conceptual question about thermoelectric energy conversion devices, specifically focusing on cooling devices.

Step 2: Key Formula or Approach:
Thermoelectric effects involve the direct conversion of temperature differences to electric voltage and vice versa.
We must distinguish between the Seebeck effect (voltage generation from temperature differences) and the Peltier effect (temperature differences generated by electric current).

Step 3: Detailed Explanation:

• Peltier Effect: When an electric current is passed through a junction of two different conductors, heat is absorbed or liberated at the junction depending on the direction of the current. This is the direct basis of thermoelectric cooling devices.

• Seebeck Effect: This is the reverse of the Peltier effect. When a temperature gradient is maintained across a junction of two different metals, an electromotive force (EMF) is generated. This is the principle behind thermocouples used for temperature measurement.

• Hall Effect: Generation of a voltage perpendicular to both an electric current and an applied magnetic field. It is used to measure magnetic fields and carrier concentrations.

• Piezoelectric Effect: Generation of electric charge in response to applied mechanical stress. It is used in pressure and acceleration sensors.

Step 4: Final Answer:
A thermoelectric cooler operates on the Peltier effect, which corresponds to Option (D).