Delhi Police Constable Exam Model Paper 2

• Wavelength: The space or length between two successive crests or troughs of a wave is called the wavelength

• It is our well known primary physical quantity known as Length
• Wavelength is represented by the Greek letter lambda (λ).

EXPLANATION

1. Vibrating in the same phase, the distance between any two nearest particles of the medium is the wavelength. So option 1 is correct.
2. Frequency: It is the number of occurrences of a repeating event per unit of time. Its SI unit is Hertz (Hz).
3. Velocity: Velocity is defined as the rate of change of displacement of a body with respect to time. The SI unit is meter per second (ms-1).

EXTRA POINTS

• Angstrom (Å), unit of length used chiefly in measuring wavelengths of light, equal to ${10}^{10}$ meter, or 0.1 nanometers.
• It is named for the 19th-century Swedish physicist Anders Jonas Ångström.
• Frequency and wavelength are inversely proportional to each other.

Velocity (v) = frequency (f) × wavelength (λ)