A heating element of a heater is made of a material with high resistivity and high melting point. Which of the following material properties is most crucial for its function as a heating element?
Show answer & explanation
Correct answer: D
Explanation
Answer: High resistivity
Explanation: A heating element works on the principle of Joule Heating, where heat is generated when electric current passes through a material. A material with high resistivity opposes the flow of current more, causing more electrical energy to be converted into heat. This makes high resistivity the most crucial property for a heating element.
Additional Key Points:
Materials like Nichrome are commonly used for heating elements.
High melting point ensures the material can withstand high temperatures without melting.
Low reactivity prevents oxidation at high temperatures.
Moderate thermal conductivity helps in uniform heat distribution.
Potential Exam-Oriented Questions & Answers:
Question: Which effect is responsible for heat production in an electric heater?
Answer: Joule Heating
Question: Why is a high melting point important for heating elements?
Answer: To withstand high temperatures without melting