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Electromagnetic Induction — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Induction3 Marks
Question
A horizontal straight wire 10m long extending from east to west is falling with a speed of $5.0ms^{–1}$, at right angles to the horizontal component of the earth’s magnetic field, $0.30 \times 10^{–4}Wbm^{–2}.$
  1. What is the instantaneous value of the emf induced in the wire?
  2. What is the direction of the emf?
  3. Which end of the wire is at the higher electrical potential?
✓

Answer

  1. Emf induced in the wire,
e = Blv
$= 0.3 \times 10^{-4} \times 5 \times 10$
$= 1.5 \times 10^{-3}V$
  1. Using Fleming's right hand rule, it can be inferred that the direction of the induced emf is from West to East.
  2. The eastern end of the wire is at a higher potential.

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