NTA Abhyas JEE Main2020PhysicsCommunication SystemPractice
The length of a dipole antenna for a carrier wave of frequency 6 × 10 8 Hz is ( take speed of EM wave 3 × 10 8 m s - 1 )
Options
- A0.25 m
- B1   m
- C2   m
- D0.1   m
Correct answer
A. 0.25 m
Step-by-step solution
Length of the antenna = λ 2 = c 2 υ ( Where c = speed of light = 3 × 10 8   m   s - 1 , υ = frequency = 6 × 10 8   Hz ) putting these values in formula above Length = 3 × 10 8 2 × 6 × 10 8 = 0 . 25   m