GK
PHYSICS
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
hysteresis loss alone
|
|
|
intense sunlight at noon
|
|
|
the heating effect of current alone
|
|
|
both the heating effect of current and hysteresis loss
|
Detailed explanation-1: -Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to both the heating effect of current and hysteresis loss.
Detailed explanation-2: -Eddy currents can be reduced by channelizing the current paths in a conductor. To do that, the core is formed by combining several insulated or laminated metal plates. Q. Statement ( A ) : Flux leakage in a transformer can be minimized by winding the primary and secondary coils one over the other.
Detailed explanation-3: -Hysteresis losses can be reduced by using material that has less area of the hysteresis loop. Hence, silica steel or CRGO steel can be used for designing the core within a transformer because it has extremely less area of the hysteresis loop.
Detailed explanation-4: -Since I0 is very small, the no-load copper loss is negligible. Hence, no-load input is practically equal to the iron loss in the transformer. Since core loss is solely responsible for shifting the current vector I0, the angle 0 is known as hysteresis angle of advance.