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(a) Figure 12 shows two circuits close to each other.
When the switch is closed, the galvanometer shows a reading in the opposite
direction and then returns to zero. Explain these observations.
(b) Explain how energy losses in a transformer are reduced by having:
(i) A soft-iron core.
(ii) A laminated core.
(c) An ideal transformer has 2000 turns in the primary circuit and 200 turns in the secondary circuit. When the primary circuit is connected to a 400V a.c source, the power delivered to a resistor in the secondary circuit is found to be 800W. Determine the current in:
(i) The secondary circuit.
(ii) The primary circuit.