What Do You Know About Light?

Explanation
The sun is the major source of light on earth. It emits light and heat through the process of nuclear fusion. The sun's rays reach the earth and provide us with the light and energy necessary for life. The moon reflects the sun's light, but it is not a source of light itself. While fire and rainbow produce light, they are not the primary sources of light on earth.

Explanation
Bioluminescence is the process by which some species of animals generate their own light. It is a biochemical reaction within the organism's body that produces light through the oxidation of a light-emitting molecule called luciferin. This phenomenon is observed in various marine organisms such as jellyfish, anglerfish, and fireflies. Bioluminescence serves different purposes for different species, including attracting mates, camouflage, and luring prey. It is a fascinating adaptation that allows these organisms to produce light without heat, making it an efficient and unique form of communication and survival strategy.

Explanation
Optics is the correct answer because it is the branch of physics that deals with the behavior and properties of light, including its interactions with matter and the instruments used to detect and measure it. It involves the study of the nature of light, its transmission, reflection, refraction, diffraction, and interference. Optics is a fundamental field of study in physics and is essential in various applications such as the design of lenses, mirrors, and optical instruments, as well as in fields like astronomy, photography, and telecommunications.

Explanation
Refraction is the correct answer because it refers to the bending of light rays when they pass through a surface between two transparent materials. This bending occurs due to the change in speed of light as it moves from one medium to another, causing the light rays to change direction.

Explanation
Radiometry is the correct answer because it is the branch of science that deals with the measurement of light power at all wavelengths. It encompasses the measurement of radiant energy, radiant flux, and other related quantities. This field is important in various applications such as astronomy, remote sensing, and optical communications. Lightometry, photometry, and photosyntolometry are not the correct answers because they either focus on specific aspects of light measurement or are not recognized terms in the field of light measurement.

Explanation
Photometry is the correct answer because it is the branch of physics that deals with the measurement of light in terms of its perceived brightness by the human eye. It involves the use of a standardized model of human brightness perception to weight the measurements of light with different wavelengths. This allows for a more accurate representation of how humans perceive light, taking into account the sensitivity of the human eye to different wavelengths. Radiometry, on the other hand, focuses on the measurement of light in terms of its physical properties, such as power or energy. Lactometry and Luminometry are not relevant to the measurement of light.

Explanation
Francesco Grimaldi is credited with discovering the diffraction of light. Diffraction is the bending or spreading of waves as they pass through an opening or around an obstacle. Grimaldi observed this phenomenon when he passed light through a narrow slit and noticed that it spread out and created a pattern of light and dark bands. His discovery laid the foundation for the understanding of wave behavior and the study of optics.

Explanation
Étienne-Louis Malus is the correct answer because he is credited with creating a mathematical particle theory of polarization. This theory, known as Malus' law, describes the intensity of light that is transmitted through a polarizer. Malus' work in the early 19th century greatly contributed to the understanding of polarization and its applications in various fields such as optics and telecommunications.

Explanation
Michael Faraday is the correct answer because he is the scientist who discovered the effect of light known as Faraday's radiation. Faraday was an English scientist who made significant contributions to the fields of electromagnetism and electrochemistry. He conducted experiments on the interaction between light and matter, and his discoveries laid the foundation for the understanding of the electromagnetic spectrum and the behavior of light. His work on Faraday's radiation helped advance our knowledge of the properties and behavior of light.

Explanation
Faraday's rotation refers to the phenomenon of the rotation of the plane of polarization of light as it passes through certain materials in the presence of a magnetic field. This phenomenon was discovered by Michael Faraday in 1845. Therefore, the correct answer is 1845.