Question

1. Write a couple (2) of paragraphs describing the origin of both the continuous background spectrum and the dark lines in the solar spectrum.

Answer 1

Isaac Newton discovered that the light coming from Sun is made up of multiple wavelengths of radiation. He observed that when the sunlight passes through the prism it divides into several colours from all the way red to violet without gap. Some believe that the colours are coming from the prism. Isaac Newton for performed an experiment in which the light coming from the prism again passes through the another prism to convert it into white light again. This experiment proved that spectrum is made up of white light coming from Sun. This is spectrum is known as continuous spectrum.

Later some experiments was done which shows that some light sources like gas discharges emits some specific wavelengths of radiation. Such radiations are called emission spectrum. Still some other experiments shows that some light sources emits nearly continuous spectrum with gapps at certain value of wavelength. This is known as absorption spectrum. Gustav kitchoff formulated three laws which describes the spectrum of all three kinds. First law says that opaque objects emit a continuous spectrum. Second law says that glowing gas emits emission spectrum. The third law says that if there is cooler gas in front of a continuous spectrum source then it will give absorption spectrum. Later Neils bohr explained the mechanisms of absorption and emission spectrum that when there is a transaction of electron from one shell to another shell then it will emit or absorb the radiation and will five the specteum accordingly. Spectral data was helpful to find many elements, like helium in Sun. Each element has its own specific spectral data which helps to determine it.