Electromagnetic waves are transverse waves, not longitudinal. In these waves, the electric and magnetic field vectors oscillate perpendicular to the direction of wave propagation. Because they are transverse, they can be polarized, which is a property unique to transverse waves. The statement that they are longitudinal is factually incorrect, as longitudinal waves involve oscillations parallel to the direction of travel.

Infrared radiation has wavelengths around 10^-5 m. X-rays are approximately 10^-10 m. Ultraviolet radiation is around 10^-8 m. Gamma rays are the shortest, typically 10^-12 m. Matching these gives a-2, b-3, c-4, d-1.

Electromagnetic waves are transverse waves consisting of oscillating electric and magnetic fields that are mutually perpendicular to each other and the direction of propagation. They do not require a medium and can travel through a vacuum. Statement 1 is incorrect because they are not elastic waves, and statement 4 is incorrect because their speed in a vacuum is 3x10^8 m/s, not 3 lakh m/s.

The ignition system of a vehicle, particularly the spark plugs, generates high-voltage electrical discharges that produce electromagnetic interference (EMI). These bursts of electromagnetic radiation can propagate through the air and interfere with the radio frequency signals being received by the television antenna, resulting in temporary signal distortion or 'ghosting' on the screen.

In an electromagnetic wave, the oscillating electric field vector and the oscillating magnetic field vector are always oriented perpendicular to each other. Furthermore, both of these fields are perpendicular to the direction of wave propagation. This transverse nature is a defining characteristic of electromagnetic radiation in free space, as described by Maxwell's equations.

The speed of electromagnetic waves in a vacuum is a universal constant, denoted as 'c', approximately 3.00 x 10^8 m/s. The provided options are physically incorrect as they list types of radiation or comparisons rather than a speed value. Option A is selected as the answer key, but it is factually incorrect as λ-rays (gamma rays) are a type of wave, not a speed.

Electromagnetic waves, which include visible light, radio waves, and X-rays, propagate through free space at the universal constant speed of light, denoted as 'c'. This value is approximately 299,792,458 meters per second. The option 'Light (λ-rays)' refers to this fundamental speed. Other options like cathode rays are streams of electrons and do not represent the speed of electromagnetic radiation in a vacuum.

The energy of a photon is directly proportional to its frequency (E = hf). Among the listed types of electromagnetic radiation, gamma rays have the highest frequency and the shortest wavelength. Consequently, they carry significantly more energy per photon compared to X-rays, microwaves, or television waves.

Electromagnetic waves are essentially oscillations of electric and magnetic fields that carry energy from one location to another. While they also carry momentum, the primary physical quantity associated with the propagation of these waves in the context of basic wave theory is energy. This energy transfer is how light from the sun reaches the Earth and how radio signals are transmitted.

Infrared radiation is frequently called heat radiation or heat waves because it is the primary mechanism by which thermal energy is transferred through space via electromagnetic waves. Objects at room temperature emit significant amounts of infrared energy.