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What are the charge carriers in (i) semiconductors and (ii) metals? - Leaving Cert Physics - Question 1 - 2014
Question 1
What are the charge carriers in (i) semiconductors and (ii) metals?
Worked Solution & Example Answer:What are the charge carriers in (i) semiconductors and (ii) metals? - Leaving Cert Physics - Question 1 - 2014
Step 1
(i) semiconductors
Answer
In semiconductors, the charge carriers are electrons and holes. Electrons represent the negative charge carriers, while holes represent the absence of an electron and act as positive charge carriers. When energy is added to a semiconductor (e.g., through heating or doping), electrons can be excited across the band gap, leaving behind holes.
Step 2
(ii) metals
Answer
In metals, the charge carriers are primarily electrons. Metals have a large number of free electrons in their structure, which facilitate electrical conductivity. These electrons are delocalized, meaning they can move freely throughout the metallic lattice, allowing for efficient conduction of electricity.