A transformer designed for a 240 V ac supply has an efficiency of 85%. Under normal operating conditions, the transformer delivers a current of 4.00 A at 18.0 V.
What is the current in the primary coil?
0.255 A0.255\text{ A}0.255 A
0.300 A0.300\text{ A}0.300 A
0.353 A0.353\text{ A}0.353 A
2.83 A2.83\text{ A}2.83 A
66 exam-style questions on AQA A Level Physics Magnetic fields (A-level only), covering Magnetic flux density (A-level only), Moving charges in a magnetic field (A-level only), Magnetic flux and flux linkage (A-level only), Electromagnetic induction (A-level only), Alternating currents (A-level only), and The operation of a transformer (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.