ECAT Pre Engineering Physics Chapter 20 MCQ Test With Answer

Top Scorers Of Physics ECAT Pre Engineering Chapter 20 Atomic Spectra MCQ`s Test

Sr.#	Question	Answer
1	The range of wavelengths of colurs in the visible colours is	A. 140 nm to 456 nm B. 10 nm to 56 nm C. 410 nm to 656 nm D. 910 nm to 956 nm
2	The first shell near the neucles is	A. L-shell B. X-shell C. N-shell D. M-shell
3	Atoms of hydrogen gas can be excited by passing electric current through it when the gas is filled into the discharge tube at a pressure which is	A. Less than atmospheric pressure B. Much less than atmospheric pressure C. Greater than atmospheric pressure D. Much greater than atmospheric pressure
4	The minimum wavelength of X-rays produced of 1KV potential difference is applied across the anode and cathode of the tube is	A. 1.24 x 10^-10m B. 7.92 x 10^-20m C. 2.78 x 10^-14m D. 3.88 x 10^-11m
5	Lyman series in the spectrum of hydrogen exists in the :	A. Infra-red region B. Visible region C. Ultraviolet region D. Both(A) and (B)
6	The results of spectra obtained by Blamer were expressed in 1896 by	A. Bohr B. Rydberg C. Planck D. Rutherford
7	The He-Ne laser discharge tube is filled with:	A. 85% He B. 15% He C. 50% He D. 60% He
8	The shell closer to the nucleus is called:	A. N shell B. L shell C. K shell D. M shell
9	Graph of Black body radiation is example of	A. Band spectra B. Continuo's spectra C. Line spectra D. All
10	X-rays produced in a tube operating at 10⁵V. The speed of X-rays produced is	A. 3 x 10⁸m/s B. 3.1 x 10⁸m/s C. 2.8 x 10⁸m/s D. 1.88 x 10⁸m/s