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	An compared to solid matter, a crack or an air bubble allows:	A. Great amount of X-rays to pass B. Smallast amount of X-rays to pass C. Very samall amount of X-rays to pass D. Any of these
2	The lasing or active medium in He-Ne laser discharge tube is:	A. Nitrogen B. Helium C. Hydrogen D. Neon
3	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
4	We can excite an atom by	A. Bombardment of particles B. Radiating photons C. Providing potential difference D. All answer are true
5	X-ray are also known as	A. Roentgen rays B. Maxwell rays C. Plank range D. Einstein rays
6	In flesh, light element like carbon, hydrogen and oxygen predominate. Three elements allows ______ amount of incident X-ray to pass through them	A. Small B. Greater C. Equal D. Sometimes
7	An electron of the hydrogen atom in the second orbit is called its:	A. Ground state B. Excited state C. Ionized state D. Any of these
8	If the distance between two charges is doubled,the force between them will become:	A. Double B. Half C. One third D. One fourth
9	Laser is a beam of:	A. Visible light B. Infra red light C. Ultra violet light D. Violet light only
10	The electric field lines start from:	A. Positive charge B. Negative charge C. Either A and B D. Neutron