Final answer:
An oscillating charge radiates an electromagnetic wave by accelerating and decelerating, which disturbs the surrounding electric and magnetic fields. Transverse electromagnetic waves are generated with electric and magnetic fields oscillating perpendicularly to the wave direction. The frequency of the radiated wave is the same as the frequency of the oscillating charge.
Step-by-step explanation:
How an Oscillating Charge Radiates an Electromagnetic Wave
When an electric charge oscillates, it accelerates and decelerates, resulting in the emission of an electromagnetic wave. As a charge speeds up and slows down, it disturbs the electric and magnetic fields in its vicinity. This oscillation generates a vibration in the fields at the same frequency as the charge's movement.
The propagation of these waves occurs as the fluctuating electric fields produce changing magnetic fields and vice versa, creating a self-sustaining wave that moves through space. The emitted wave is typically a transverse wave, with the electric field oscillating perpendicular to the direction of wave travel and the magnetic field oscillating perpendicular to both the wave direction and the electric field.
The relationship between the frequency of the radiated electromagnetic wave and the frequency of the oscillating charge is direct. The frequency (v or f) at which the charge oscillates is exactly the same as the frequency of the electromagnetic wave it generates. Therefore, if the oscillation frequency of the charge changes, the frequency of the produced electromagnetic wave changes in tandem.
In the case of an antenna transmitting radio waves, the alternating current applied to the antenna has a specific frequency. This current causes electrons within the antenna to oscillate at that frequency, leading to the emission of electromagnetic waves at the same frequency. The length of the antenna is typically related to the wavelength (λ) of the desired radio waves, often being half the wavelength to enhance radiation efficiency through standing waves.