The power radiated from a linear antenna of length \( l \) is proportional to: (Given, \( \lambda \) = Wavelength of wave):
- $\frac{l}{λ}$
- $\frac{l}{λ^2}$
- $\left(\frac{l}{λ}\right)^2$
- $\frac{l^2}{λ}$
The Correct Option is C
Solution and Explanation
The power radiated by a linear antenna is proportional to the square of the current and the square of the antenna's length. Additionally, the radiated power depends inversely on the square of the wavelength of the electromagnetic wave. Thus, the proportionality relation is: \[ P \propto \left( \frac{l}{\lambda} \right)^2. \]
Final Answer: The power radiated from a linear antenna is proportional to: \[ \boxed{\left( \frac{l}{\lambda} \right)^2}. \]
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