Electronics and Communication Engineering - Materials and Components

11.

Assertion (A): If an atom of polarizability a is placed in homogeneous field E, the energy stored is 0.5 aE2.

Reason (R): Capacitance of an isolated conducting sphere R in vacuum is 4 p0 R farads.

Both A and R are true and R is correct explanation of A
Both A and R are true but R is not correct explanation of A
A is true but R is false
A is false but R is true
Answer: Option
Explanation:
No answer description is available. Let's discuss.

12.
Which of the following are true for relative dielectric constant?
  1. It is dimensionless.
  2. It is equal to 1 for vacuum.
  3. It is equal to 1 for all substances.
1 and 2 only
2 and 3 only
1 and 3 only
1, 2 and 3
Answer: Option
Explanation:

r has no units and equal to 1 for vacuum. For other substances it has different value.


13.
Schrodinger wave equation is partial differential equation.
True
False
Answer: Option
Explanation:
No answer description is available. Let's discuss.

14.
Hall effect is observed in a specimen (metal or semi- conductor) when it is carrying current and is placed in a magnetic field. The resultant electric field inside the specimen is
normal to both current and magnetic field
in the same direction as current
in a direction anti parallel to magnetic field
none of the above
Answer: Option
Explanation:
No answer description is available. Let's discuss.

15.
The capacitance of a capacitor is not affected by
area of plates
thickness of plates
r
distance between plates
Answer: Option
Explanation:

Capacitance depends on area, distance and ∈r but not on thickness of plates.