Wavelength and frequency of a radio wave are 12 m and 25 × 106 Hz respectively. Calculate its velocity.
The velocity of a wave, including a radio wave which is an electromagnetic wave, is related to its frequency and wavelength by a fundamental formula.
The relationship is given by:
$\text{Velocity} = \text{Frequency} \times \text{Wavelength}$
In terms of symbols:
$v = \nu \lambda$
Where:
In this problem, we are given the following values for the radio wave:
Now, we can substitute these values into the formula to calculate the velocity of the radio wave.
The calculated velocity of the radio wave is $3 \times 10^8$ m/s. This value is approximately the speed of light in a vacuum, which is expected for electromagnetic waves like radio waves.
Comparing this result with the given options, we find that it matches option 2.
Ultrasonic pulse echo technique, a non-destructive ultrasonic testing, is employed for any possible flaw detection in a metallic bar of thikness 30 cm. If the arrival times of the ultrasonic pulses are 45 μs and 90 μs respectively, the distance of the flaw from one end of the steel bar at which the ultrasonic pulse initially enters the steel bar, will be:
In which of the following medium, velocity of light is maximum?