Question

7. A piece of silver and another of silicon are
heated from room temperature. The
resistance of
1) each of them increases
2) each of them decreases
3) Silver increases and Silicon decreases
4) Silver decreases and Silicon increases​

Answer 1

Answer:

3

We know that: R

=

ρ

L

A

(Both pieces are assumed to be similar i.e.

L

and

A

will be same for both so

R

directly depends upon

ρ

)

Thermal resistivity

ρ

for metals is positive and that for semiconductors is negative.

∴

when an element is heated, if it is a metal then resistance increase and if it is a semiconductor then resistance decreases.