Question

After a long time ^_^

Question = Name any three substance whose resistance decreases with increase in their temperature ☺?

Note = Question is from chapter Current Electricity of class 12th ​

Answer 1

Answer:

Explanation:

Resistance of semi conductors such as germanium, selenium, silicon decreases with temperature because more covalent bonds in semiconductor get broken with rise of temperature providing more number of electrons and holes as current carriers

Answer 2

Answer:

The most common of substances that portray this property are metal alloys such as Manganin, German-silver and constantan. 

This phenomenon is due to altered metal properties of the individual metals such as fermin energy. Mercury, Nichrome, Platinum etc are examples of substances that have a low temperature coefficient. And thus their resistances changes very little with the rise in temperature.

Hope it helps! :)