⚛️ Physics · Electromagnetic Induction · NEET & JEE

A transformer has 500 turns in its primary and 2000 turns in its secondary. The primary is connected to 100 V AC and the secondary supplies a 200 Ω load. If the transformer is ideal, the current drawn from the primary is:

Answer: 8.00 A.

A 0.50 A
B 2.00 A
C 8.00 A
D 4.00 A

Correct answer: C. 8.00 A

Explanation: Secondary voltage = 100 × 2000/500 = 400 V. Secondary current = 400/200 = 2 A. Input power is conserved, so primary current = 400 × 2/100 = 8 A.

As a magnet approaches a coil, flux rises steadily and a constant non-zero EMF is induced (Faraday's law). Once the magnet stops moving, flux stays constant and the induced EMF drops to zero - EMF only exists while flux is actively changing.

Concept context

Faraday's and Lenz's laws, motional EMF, self/mutual inductance, eddy currents, and the AC generator - how a changing magnetic flux creates an electric current.

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A transformer has 500 turns in its primary and 2000 turns in its secondary. The primary is connected to 100 V AC and the secondary supplies a 200 &Omega; load. If the transformer is ideal, the current drawn from the primary is:

Concept context

More Electromagnetic Induction questions

A transformer has 500 turns in its primary and 2000 turns in its secondary. The primary is connected to 100 V AC and the secondary supplies a 200 Ω load. If the transformer is ideal, the current drawn from the primary is: