(a)
The explanation for the optical properties of metal.
(a)
Answer to Problem 1Q
Metals are opaque to visible light.
Explanation of Solution
Metals can absorb visible light. Again, visible can be scattered by the free electron inside the metal. As a result visible light can be easily absorbed by the metals.
Hence, Metals are opaque to the visible light.
(b)
The explanation for the optical properties of semiconductor.
(b)
Answer to Problem 1Q
Semiconductors are opaque to visible light however transparent to infrared.
Explanation of Solution
For semiconductor, the valance band can absorb the visible light as it has enough energy. As a result, the electrons can move from valance band to
On other hand, the infrared is not has enough energy to get absorb by semi-conductor. Hence,
(c)
The explanation for the optical properties of insulator.
(c)
Answer to Problem 1Q
Many insulators are transparent to visible light.
Explanation of Solution
The visible light has not has enough energy to get absorb by insulator. As a result, the electron from valance will not able to move to conduction band. Hence, the visible light can only pass through the insulator, like diamond.
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Chapter 12 Solutions
EBK MODERN PHYSICS
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