Question
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from thecodes(a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion: Silicon is preferred over germanium for making semiconductor devices.
Reason: The energy band for germanium is more than the energy band of silicon.

Answer

  1. A is false and R is also false.
Explanation:
The energy gap for germanium is less (0.72eV) than the energy gap of silicon (I.IeV). Therefore, germanium is preferred over silicon for making semiconductor devices.

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