The core of a coil has a length of 10 cm. The self inductance is 8 mH. If the co

CuriousTab

CuriousTab

Home Aptitude

Discussion

Home ‣ Electronics and Communication Engineering ‣ Materials and Components See What Others Are Saying!

Question
The core of a coil has a length of 10 cm. The self inductance is 8 mH. If the core length is doubled, all other quantities remaining the same, the self inductance will be
Options
A. 32 mH
B. 16 mH
C. 8 mH
D. 4 mH

Correct Answer

4 mH

Explanation

Inductance is inversely proportional to the core length.

More questions

1. In an integral controller
Options
A. the output is proportional to input
B. the rate of change of output is proportional to input
C. the output is proportional to rate of change of input
D. none of the above

2. Wave A = 100 sin ?t and wave B = 100 cos ?t. Then
Options
A. rms values of the two waves are equal
B. rms values of A is more than that of B
C. rms values of A is less than that of B
D. rms values of the two waves may or may not be equal

6. The terminals of a power MOSFET are called
Options
A. emitter, base, collector
B. source, gate, drain
C. source, base, drain
D. emitter, gate, drain

7. A JK flip flop has t_pd= 12 ns. The largest modulus of a ripple counter using these flip flops and operating at 10 MHz is
Options
A. 16
B. 64
C. 128
D. 256

8. In a two phase ac servomotor rotor resistance is R and rotor reactance is X. The speed curve will be linear if
Options
A.
B.
C.
D. X² = R

10. Regarding TASI which one of the following statements is wrong?
Options
A. It snatches the channel in his speech and may allocate it to another speaker needing it.
B. The same speaker is reassigned a channel almost instantly when he speaks again even when the circuit is heavily loaded.
C. It increases the overall utilization of the transmission channel
D. Intercontinental callers sometimes confuse the effects of TASI with the effects of satellite delay.

Comments

There are no comments.

More in Electronics and Communication Engineering: