A transmission line of length 3λ/4 and having a characteristic ...
A transmission line of length 3 refers to a transmission line that is 3 units long. The length of a transmission line is measured in terms of wavelength or physical distance.
In the context of electromagnetic waves, the length of a transmission line is usually given in terms of wavelength. The wavelength of a wave is the distance between two consecutive points of the same phase, such as two crests or two troughs. Wavelength is denoted by the symbol λ (lambda) and is measured in meters or any other unit of length.
Therefore, a transmission line of length 3 in terms of wavelength implies that the length of the transmission line is 3 times the wavelength of the corresponding electromagnetic wave.
On the other hand, if the length of the transmission line is given in terms of physical distance, such as meters or feet, then a transmission line of length 3 would simply mean that the physical length of the transmission line is 3 units long.
It's important to note that the specific characteristics of a transmission line, such as impedance, propagation speed, and reflection coefficients, depend not only on its physical length but also on its design, material properties, and termination conditions.