What device is used to produce electrical potential by heating two dissimilar metals?

• A. thermocouple
• B. photovoltaic cell
• C. resistor
• D. inductor

Answer: (A)

The device that produces electrical potential by heating two dissimilar metals is a thermocouple. A thermocouple consists of two different metal wires joined at one end. When the joined end is heated, it creates a voltage difference due to the thermoelectric effect, which is the principle that allows the generation of electricity from temperature differences. The Seebeck effect, a specific phenomenon within the thermoelectric effect, explains how this voltage is produced when two different metals are subjected to a temperature gradient.

In contrast, photovoltaic cells convert light energy directly into electrical energy through the photovoltaic effect, not involving heat or two metals. Resistors and inductors are passive electrical components that do not generate electrical potential; instead, resistors limit current flow and dissipate energy, while inductors store energy in a magnetic field when electric current passes through them. Hence, the thermocouple is distinctively the correct choice for the question regarding the production of electrical potential through heating dissimilar metals.