The hum in a transformer is mainly attributed to______________?
The hum in a transformer is mainly attributed to______________?
A. load changes
B. oil in the transformer
C. magnetostriction
D. mechanical vibrations
Similar Posts
The purpose of providing iron core in a step-up transformer is?
The purpose of providing iron core in a step-up transformer is?A. to provide coupling between primary and secondary
B. to increase the magnitude of mutual flux
C. to decrease the magnitude of mag-netizing current
D. to provide all above featuresTwo transformers operating in parallel will share the load depending upon their____________?
Two transformers operating in parallel will the load depending upon their____________?
A. leakage reactance
B. per unit impedance
C. efficiencies
D. ratingsWhich of the following does not change in an ordinary transformer ?
Which of the following does not change in an ordinary transformer ?
A. Frequency
B. Voltage
C. Current
D. Any of the aboveMinimum voltage regulation occurs when the power factor of the load is_____________?
Minimum voltage regulation occurs when the power factor of the load is_____________?
A. unity
B. lagging
C. leading
D. zeroA shell-type transformer has_________?
A shell-type transformer has_________?
A. high eddy current losses
B. reduced magnetic leakage
C. negligibly hysteresis losses
D. none of the aboveSumpner’s test is conducted on transformers to determine_____________?
Sumpner’s test is conducted on transformers to determine_____________?
A. temperature
B. stray losses
C. all-day efficiency
D. none of the above