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Electromagnetic Waves — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Waves3 Marks
Question
  1. Identify the part of the electromagnetic spectrum which is:
  1. Suitable for radar system used in aircraft navigation,
  2. Produced by bombarding a metal target by high-speed electrons.
  1. Why does a galvanometer show a momentary deflection at the time of charging or discharging a capacitor? Write the necessary expression to explain this observation.
✓

Answer

  1.  
  1. Microwaves.
  2. X-rays.
  1. Due to conduction current in the connecting wires and a displacement current between the plates $\text{I}_{d} = \in_{o}\frac{\text{d}\phi_{\text{E}}}{\text{dt}}.$

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