Who proved that blue light was indeed more efficient that red light?

In chemistry at that time there was a rumour that blue light was more efficient at initiating chemical change than red light. Ritter tried to measure the speed at which silver chloride broke down with different colours. He proved that blue light was indeed more efficient that red light.

Who discovered ultraviolet radiation?

On 22 February 1801, Johann Wilhelm Ritter discovered UV radiation in Jena. In general, this achievement is less well known than his work on galvanism. Ritter was the creator of modern electrochemistry.

Why is UV light harmful but infrared is not?

The energy represented by an individual photon is a function of its frequency. UV photons are higher frequency radiation than infrared. UV rays have a high enough frequency to ionize molecules when they hit them; IR rays do not. That ionization causes DNA damage and by extension mutations.

Which ultra violet light has the most energy and therefore is the most harmful?

UV-C
Ultraviolet rays can be subdivided into three different wavelength bands – UV-A, UV-B, and UV-C. This is simply a convenient way of classifying the rays based on the amount of energy they contain and their effects on biological matter. UV-C is most energetic and most harmful; UV-A is least energetic and least harmful.

Who predicted the existence of electromagnetic waves?

physicist James Clerk Maxwell
The results of these experiments were synthesized in the 1850s by the Scottish physicist James Clerk Maxwell in his electromagnetic theory. Maxwell’s theory predicted the existence of electromagnetic waves–undulations in intertwined electric and magnetic fields, traveling with the velocity of light.

Who found electromagnetic waves?

About 150 years ago, James Clerk Maxwell, an English scientist, developed a scientific theory to explain electromagnetic waves. He noticed that electrical fields and magnetic fields can couple together to form electromagnetic waves.

Why is UV more damaging to your skin than IR?

In terms of wavelength, ultraviolet radiation has shorter wavelengths than visible radiation, which have shorter wavelengths than infrared. Of more importance to us, ultraviolet photons have enough energy to damage or destroy DNA, visible and infrared photons do not.

Why is UV light so lethal to living cells?

Basically, UV kills cells because of the accumulation of DNA damage. A gene product, called p53, is one of the responsible parties for slowing the cell cycle and checking for damage. If the damage is too extensive, it directs the cell to apoptosis, or programmed cell death.

What does the C in UVC stand for?

ultraviolet C (UVC) ultraviolet radiation with wavelengths between 200 and 290 nm; all of this type of radiation is filtered out by the ozone layer so that none reaches the earth’s surface.

What nm is UVC?

200 to 280 nm
UV light covers a wavelength spectrum from 100 to 380 nm and is subdivided into three regions by wavelength: UVA (320 to 400 nm), UVB (280 to 320 nm), and UVC (200 to 280 nm) (1). Among them, UVC has the strongest germicidal effect and is widely used in the form of mercury lamps to inactivate microorganisms.

What did Max Planck contribute to theoretical physics?

Planck made many contributions to theoretical physics, but his fame as a physicist rests primarily on his role as the originator of quantum theory, which revolutionized human understanding of atomic and subatomic processes.

What did Max Planck discover about black matter?

Lesson Summary. Max Planck was a German scientist who first discovered that energy is emitted from a black body in discrete amounts called quanta. He showed that the amount of energy was proportional to the frequency of the radiation that was absorbed by the black body, a relationship now known as Planck’s Law.

What is the relationship given by Planck’s radiation law?

The relationship given by Planck’s radiation law, given below, shows that with increasing temperature, the total radiated energy of a body increases and the peak of the emitted spectrum shifts to shorter wavelengths. According to this, the spectral radiance of a body for frequency ν at absolute temperature T is given by

What is Planck’s theory of the electromagnetic spectrum?

In 1900, Max Planck heuristically derived a formula for the observed spectrum by assuming that a hypothetical electrically charged oscillator in a cavity that contained black-body radiation could only change its energy in a minimal increment, E, that was proportional to the frequency of its associated electromagnetic wave.