The wavelength of the electromagnetic wave having frequency of 3 kHz will be?
Correct answer: B. 100 km
- A. 120 km
- B. 100 km
- C. 80 km
- D. 140 km
Explanation
λ = v / fInputting speed of light or 3 x 108 m/s as v and 3 x 103 Hz as f gives us 1 x 105 m or 100 km.
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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