[{"id":253948,"question":"The potential difference applied to an X-rays tube is increased. As a result, in the emitted radiation","choices":[{"text":"The intensity increases","value":"A"},{"text":"The minimum wavelength decrease","value":"B"},{"text":"The intensity remains unchanged","value":"C"},{"text":"Both B &amp; C","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253947,"question":"Light of frequency 4f0 is incident on the metal of the threshold frequency f0. The maximum kinetic energy of the emitted photoelectrons is","choices":[{"text":"3h f0","value":"A"},{"text":"3/2h f0","value":"B"},{"text":"2h f0","value":"C"},{"text":"1/2h f0","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253946,"question":"Figure represents a graph of kinetic energy (K) of the photoelectrons (in eV) and frequency (v) for a metal used as cathode in photoelectric experiment. The work function of metal is:","choices":[{"text":"1 eV","value":"A"},{"text":"2 eV","value":"B"},{"text":"1.5 eV","value":"C"},{"text":"3 eV","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253945,"question":"The ratio of the longest and shortest wavelength of the Lyman series is approximately:","choices":[{"text":"4/3","value":"A"},{"text":"9/4","value":"B"},{"text":"9/5","value":"C"},{"text":"16/7","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253944,"question":"According to Bohr’s theory, a line in the Ballmer series arises when the electron jumps from any of the higher orbits to the orbit with quantum number:","choices":[{"text":"1","value":"A"},{"text":"2","value":"B"},{"text":"3","value":"C"},{"text":"4","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253943,"question":"In which region of the electromagnetic spectrum does the Lyman series of hydrogen atom lie?","choices":[{"text":"Infrared","value":"A"},{"text":"Visible","value":"B"},{"text":"Ultraviolet","value":"C"},{"text":"X-rays","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":253942,"question":"A proton and an 𝑎 − 𝒑𝒂𝒓𝒕𝒊𝒄𝒍𝒆 are accelerated through same voltage, the ratio of their de- Broglie wavelength will be:","choices":[{"text":"1:2","value":"A"},{"text":"√2: 1","value":"B"},{"text":"2√2: 1","value":"C"},{"text":"2:1","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":253941,"question":"The de-Broglie wavelength of the particle of mass m and energy E is:","choices":[{"text":"","img":"253941_638248487187600258-RA1.png","value":"A"},{"text":"ℎ","value":"B"},{"text":"𝜆 = ℎ√2𝑚𝐸","value":"C"},{"text":"𝜆 =<span style=\"white-space:pre\">\t</span>1","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253940,"question":"Threshold wavelength for metal having work function 𝝋 is 𝝀. What is the threshold wavelength for metal having work function 2 𝒊𝒔:","choices":[{"text":"/𝟐","value":"A"},{"text":"2","value":"B"},{"text":"4","value":"C"},{"text":"𝝀/𝟒","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253939,"question":"When ultraviolet rays are incident in metal plate, then photoelectric effect does not occur. It occurs by the incidence of:","choices":[{"text":"x-rays","value":"A"},{"text":"Infrared rays","value":"B"},{"text":"Radio wave","value":"C"},{"text":"Greenhouse effect","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253938,"question":"The hydrogen atoms are excited to the stationary state designated by the principal quantum number n=4, the number of maximum spectral lines are observe:","choices":[{"text":"2","value":"A"},{"text":"3","value":"B"},{"text":"4","value":"C"},{"text":"6","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253937,"question":"A proton, accelerated through a p.d V has a certain de Broglie wavelength. In order to have the same de Broglie wavelength, an 𝑎 −particles must be accelerated through a potential difference:","choices":[{"text":"4V","value":"A"},{"text":"8V","value":"B"},{"text":"V/4","value":"C"},{"text":"V/8","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253936,"question":"As the intensity of incident light increases:","choices":[{"text":"Photoelectric current increases","value":"A"},{"text":"Photoelectric current decreases","value":"B"},{"text":"Kinetic energy of emitted photoelectrons increases","value":"C"},{"text":"Kinetic energy of emitted photoelectrons decreases","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253935,"question":"To find longest wavelength radiation in Ballmer series, the value of n used is:","choices":[{"text":"2","value":"A"},{"text":"3","value":"B"},{"text":"4","value":"C"},{"text":"∞","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253934,"question":"Maximum speed of electrons in X-rays tube which is producing X-rays photons of frequency f is","choices":[{"text":"","img":"253934_638248479693363477-RA1.png","value":"A"},{"text":"","img":"253934_638248479693363477-RA2.png","value":"B"},{"text":"","img":"253934_638248479693363477-RA3.png","value":"C"},{"text":"","img":"253934_638248479693363477-RA4.png","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253881,"question":"J.J Thomson finds:","choices":[{"text":"Particle nature of the electron","value":"A"},{"text":"Dual nature of electron","value":"B"},{"text":"Wave nature of electron","value":"C"},{"text":"Electromagnetic nature of electron","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253880,"question":"G.P Thomson revealed:","choices":[{"text":"Particle nature of electron","value":"A"},{"text":"Dual nature of electron","value":"B"},{"text":"Wave nature of electron","value":"C"},{"text":"Electromagnetic nature of electron","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253879,"question":"Interference and diffraction of light confirms its:","choices":[{"text":"Particle nature","value":"A"},{"text":"Dual nature","value":"B"},{"text":"Wave nature","value":"C"},{"text":"Electromagnetic nature","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":253878,"question":"Davisson and Germer received the Nobel prize for their work on:","choices":[{"text":"Wave nature of particle","value":"A"},{"text":"Corpuscular nature of wave","value":"B"},{"text":"Dual nature of particle","value":"C"},{"text":"All of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253877,"question":"De-Broglie received the Nobel prize on his work on:","choices":[{"text":"Wave nature of particle","value":"A"},{"text":"Corpuscular nature of wave","value":"B"},{"text":"Dual nature of particle","value":"C"},{"text":"All of them","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":253876,"question":"De-Broglie received the Nobel prize in","choices":[{"text":"1929","value":"A"},{"text":"1937","value":"B"},{"text":"1928","value":"C"},{"text":"1924","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253875,"question":"Diffraction pattern has also been observed for:","choices":[{"text":"Proton","value":"A"},{"text":"Neutron","value":"B"},{"text":"Hydrogen atom","value":"C"},{"text":"All of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253874,"question":"In order to perform experiment, Davisson and Germer used accelerating voltage of:","choices":[{"text":"54V","value":"A"},{"text":"120V","value":"B"},{"text":"220V","value":"C"},{"text":"400V","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253873,"question":"Davisson and Germer, in their experiment used:\r\n","choices":[{"text":"Nickle crystal","value":"A"},{"text":"Lead crystal","value":"B"},{"text":"Graphite crystal","value":"C"},{"text":"Glass","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253872,"question":"Which of the particles, electron, proton and neutron moving with same speed has longest wave length?","choices":[{"text":"Electron","value":"A"},{"text":"Proton","value":"B"},{"text":"Neutron","value":"C"},{"text":"All have same","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253871,"question":"Interference and diffraction confirm:","choices":[{"text":"Particle nature","value":"A"},{"text":"Wave nature","value":"B"},{"text":"Dual nature","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253870,"question":"The number of electrons emitted depend upon","choices":[{"text":"Colour of target surface","value":"A"},{"text":"Shape of surface","value":"B"},{"text":"Frequency of incident light","value":"C"},{"text":"Intensity of incident light","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253869,"question":"Rest mass energy of electron is:","choices":[{"text":"1.02 MeV","value":"A"},{"text":"0.51 MeV","value":"B"},{"text":"931 MeV","value":"C"},{"text":"200 MeV","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253868,"question":"In photoelectric effect, if we increase the frequency of the incident light then of the electrons\r\nincreased","choices":[{"text":"Number","value":"A"},{"text":"K.E","value":"B"},{"text":"P.E","value":"C"},{"text":"Frequency","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253867,"question":"The unit of work function is","choices":[{"text":"eV","value":"A"},{"text":"Volt","value":"B"},{"text":"Farad","value":"C"},{"text":"Herdz","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253866,"question":"The maximum kinetic energy of emitted photoelectrons depends upon:","choices":[{"text":"The intensity of incident light","value":"A"},{"text":"Frequency of incident light","value":"B"},{"text":"Metal surface","value":"C"},{"text":"Both frequency of incident light and metal surface","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":253865,"question":"In order to increase the K.E of ejected photo electrons, there should be an increase in:","choices":[{"text":"Intensity of radiation","value":"A"},{"text":"NoneI","value":"B"},{"text":"Frequency of radiation","value":"C"},{"text":"Both (b) &amp; (c)","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":253864,"question":"The reverse process of photo-electric effect is called:","choices":[{"text":"Pair production","value":"A"},{"text":"Compton effect","value":"B"},{"text":"Annihilation of matter","value":"C"},{"text":"X-rays","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253863,"question":"Potassium cathode in photocell emits electrons for a light:","choices":[{"text":"Visible","value":"A"},{"text":"Infrared","value":"B"},{"text":"Ultraviolet","value":"C"},{"text":"X-rays","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253862,"question":"Photoelectric effect and Compton effect prove the:","choices":[{"text":"Wave nature of light","value":"A"},{"text":"Particle nature of light","value":"B"},{"text":"Dual nature of light","value":"C"},{"text":"Dual nature of light","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253861,"question":"Compton Effect makes the use of the law of conservation of:","choices":[{"text":"Energy","value":"A"},{"text":"Momentum","value":"B"},{"text":"Charge","value":"C"},{"text":"Both (a) &amp; (b)","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253860,"question":"The unit Compton wavelength is same as:","choices":[{"text":"Compton wavelength","value":"A"},{"text":"Compton frequency","value":"B"},{"text":"Compton shift","value":"C"},{"text":"Both (a) &amp; (b)","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":253859,"question":"In Compton effect, it was considered that X-rays consist of:","choices":[{"text":" Electrons","value":"A"},{"text":"Positrons","value":"B"},{"text":"Photons","value":"C"},{"text":"All of these","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253858,"question":"A.H Compton studied the scattering of X-rays by loosely bound electrons from a graph target in:","choices":[{"text":"1905","value":"A"},{"text":"1911","value":"B"},{"text":"19251","value":"C"},{"text":"1923","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":253857,"question":"Photo cells is a device which convert light into:","choices":[{"text":"Wave nature","value":"A"},{"text":"Particle nature","value":"B"},{"text":"Particle wave nature","value":"C"},{"text":"Dual nature","value":"D"},{"value":"E"}],"correctAnswer":2}]