State desirable properties of heating elements used in indirect resistance heating.

State desirable properties of heating elements used in indirect resistance heating. 
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Answer :

Following properties of good heating material in indirect resistance heating:- 1. High resistivity: It should have high resistivity. So that it becomes compact in size and produces more heat with small input current. 2. High melting point: It should have high melting point to withstand at high temperature. 3. High Oxidizing temperature: It should have high oxidizing temperature or it should not oxidize even at high temperature. 4. High Resistance to corrosion: It should have high resistance to corrosion to avoid rusting. 5. High Mechanical Strength: It should have high mechanical strength to withstand from mechanical injury. 6. Ductile: It should be ductile so that it can be manufactured into different size & shape. 7. Long Life: It should have long life. 8. Less Costly: It should be less costly and easily available. 9. Low temperature co-efficient of resistance: For accurate temperature control, it should have low temperature co-efficient of resistance. 10.It should not be brittle.

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