The temperature coefficient of a thermistor is positive is negative zero may be

CuriousTab

CuriousTab

Home Aptitude

Discussion

Home ‣ Electronics and Communication Engineering ‣ Materials and Components Comments

Question
The temperature coefficient of a thermistor
Options
A. is positive
B. is negative
C. zero
D. may be positive or negative depending on its composition

Correct Answer

is negative

Materials and Components problems

Search Results

1. A liquid has N permanent dipoles ?_p per unit volume and has been subjected to dc field for a long time such that orientation polarization is P₀. At t = 0, the field is suddenly removed, then polarization
Options
A. will remain constant at P₀
B. will become zero at t = 0
C. will delay to zero with a time constant
D. either b or c

2. Assertion (A): Ferromagnetic materials possess ferromagnetic properties only when temperature is less than paramagnetic curie temperature.
Reason (R): For a ferromagnetic material for T > ?_f.
Options
A. Both A and R are true and R is correct explanation of A
B. Both A and R are true but R is not correct explanation of A
C. A is true but R is false
D. A is false but R is true

3. In carbon resistor colour code, if the third band is of silver, it indicates
Options
A. that three zeros are to be added to indicate the resistance value
B. multiplier is 0.01
C. multiplier is 0.1
D. tolerance is � 5%

5. The orientation polarization is
1. directly proportional to temperature
2. inversely proportional to temperature
3. inversely proportional to square of permanent dipole moment
4. directly proportional to square of permanent dipole moment.
Which of the above are correct?
Options
A. 1 and 3 only
B. 2 and 3 only
C. 1 and 4 only
D. 2 and 4 only

7. As per Bohr's postulate, only those circular orbits are stable for which the angular momentum is equal to an integer times .
Options
A. True
B. False

9. In a specimen of silicon steel, a field strength of 200 A/m causes a flux density of 0.5 T. In a specimen of cast iron, the same H would cause B to be
Options
A. 0.5 T
B. less than 0.5 T
C. more than 0.5 T
D. 0.5 T or more or less

Comments

More in Electronics and Communication Engineering: