Using supplied value of μ ∘ and ε ∘ , find the speed of electromagnetic waves in vacuum.

The value of permeability of free space: μ ∘ = 4 π × 10 - 7 T m A - 1 The value of permittivity of free space: ε ∘ = 8 . 86 × 10 - 12 C 2 N - 1 m - 2 The velocity of propagation of an electromagnetic wave in vacuum will be: c = 1 μ ∘ ε ∘ = 1 4 π × 10 - 7 T m A - 1 8 . 86 × 10 - 12 C 2 N - 1 m - 2 = 2 . 998 m s - 1 Hence, the speed of the electromagnetic waves in vacuum is 2 . 998 m s - 1 .

Using supplied value of μ ∘ and ε ∘ , find the speed of electromagnetic waves in vacuum.

The value of permeability of free space: μ ∘ = 4 π × 10 - 7 T m A - 1 The value of permittivity of free space: ε ∘ = 8 . 86 × 10 - 12 C 2 N - 1 m - 2 The velocity of propagation of an electromagnetic wave in vacuum will be: c = 1 μ ∘ ε ∘ = 1 4 π × 10 - 7 T m A - 1 8 . 86 × 10 - 12 C 2 N - 1 m - 2 = 2 . 998 m s - 1 Hence, the speed of the electromagnetic waves in vacuum is 2 . 998 m s - 1 .

State two applications each of X-rays and radio waves.

X-rays are used in medical sector for the diagnostics of fracture or diseased organ, and are also used by military or the police to scan any vehicle or container for the presence of bomb or any unwanted item. Radio waves are used in transmission of radio signals for communication and radar navigation.

Write the following radiations in the ascending order of their wavelengths: Microwaves, Ultraviolet rays, Gamma rays, Infrared rays

So, the wavelength of the given radiations are as follows: Microwaves: 1 mm - 25 μm Ultraviolet rays: 400 nm - 1 nm Gamma rays: less than 10 pm Infrared rays: 25 μm - 2 . 5 μm Thus, the list of radiation in ascending order of their wavelengths is as follows: Gamma rays, Ultraviolet rays, Infrared rays, Microwaves.