A transformer operates at 100% efficiency with a 200 V primary supply and a 50 Ω load on the secondary. If the primary current is 2 A, the secondary voltage is:
Correct answer: B. 100 V
- A. 50 V
- B. 100 V
- C. 200 V
- D. 400 V
Explanation
For an ideal transformer, power in = power out: VpIp = VsIs. Given Vp = 200 V, Ip = 2 A, power = 200 × 2 = 400 W. Thus, VsIs = 400, and Is= Vs/50. Solving Vs ²/50 = 400, Vs² = 20000, Vs = 100 V.
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Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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