Which of the following produces electromagnetic waves?
Show Hint
- Stationary charges
- Charges in uniform motion
- Accelerating charges
- Stationary magnet
The Correct Option is C
Approach Solution - 1
Electromagnetic waves are produced by accelerating charges. This is a fundamental concept in electromagnetism, where oscillating or accelerating charges generate time-varying electric and magnetic fields that propagate through space as electromagnetic waves.
Step 1: When charges are stationary, they produce electric fields, but no magnetic field, hence they do not generate electromagnetic waves.
Step 2: Charges in uniform motion create a constant magnetic field and may generate electromagnetic radiation if they are moving in a changing manner, but only accelerating charges produce the full electromagnetic wave.
Step 3: The correct answer is that accelerating charges produce electromagnetic waves as described by Maxwell's equations.
Approach Solution -2
To determine which option produces electromagnetic waves, we need to understand the nature of electromagnetic wave generation. Electromagnetic waves are produced by accelerating charges. Let us examine the options:
- Stationary charges: Charges at rest do not produce electromagnetic waves since there is no change in their electric field.
- Charges in uniform motion: Charges moving at constant velocity create a steady magnetic field but do not produce electromagnetic waves because the fields do not change with time.
- Accelerating charges: When charges accelerate, they produce time-varying electric and magnetic fields, which propagate away from the charges as electromagnetic waves.
- Stationary magnet: A stationary magnet has a constant magnetic field, but like stationary charges, it does not produce electromagnetic waves as there is no time-varying field.
Therefore, accelerating charges are the source of electromagnetic waves.
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