A laboratory power transformer is provided with two identical secondary windings
PHYSICS · Multi-part · CBSE · Physics · Alternating Current · Alternating Current
Problem
A laboratory power transformer is provided with two identical secondary windings, each rated at 12 V, 4.0 A (rms). The transformer is to be operated from a 230 V, 50 Hz mains supply and may be treated as ideal.
(i) If the two secondary windings are connected in series so that their emfs add, find the secondary voltage and the maximum load current that can be drawn safely.
(ii) If instead the two secondary windings are connected in parallel so that their currents add, determine the secondary voltage and the maximum load current available.
(iii) For each of the two connections above, calculate the corresponding primary current drawn from the 230 V supply when the maximum rated secondary current flows.
(iv) A device requires 24 W at 12 V for proper operation. Which secondary connection would you choose to run the device? Give a quantitative justification for your choice.