Ans. Fluorescent materials emit light only so long as light is incident on them. An electron has kinetic energy equal to 100eV. Threshold frequency – The minimum values of frequency of the incident light below which photoelectric emission is not possible is called as threshold frequency. For every metal, there exists a certain minimum frequency below which no photoelectric effect occurs. 2.Mention one physical process for the release of electron from the surface of a metal? The maximum kinetic energy of the photoelectrons is independent of light intensity, but increases with increasing the frequency of incident light. The first type of scattered wave has same wavelength (λ, ) as the incoming X-rays, while second type has a longer wavelength (λ) than incident rays (First type of X-rays are called unmodified x-rays, while second type of X-rays are called modified X-rays.) . Another vacancy is now created in the ‘L’ shell which is again filled up by another electron jump from one of the upper shell (M) which results in the emission of another photon, but of different X-rays frequency. So, Davisson and Germer experiment was consistent with De Broglie’s hypothesis. Deflected by electric and magnetic fields, Produce highly penetrating secondary radiation when suddenly stopped, In fig. Class 12 NCERT/CBSE board notes for Dual Nature Of Matter And Radiation. By how much would the stopping potential for a given photosensitive surface go up if the frequency of the incident radiations were to be increased from 41015 Hz to 8  1015 Hz? Metal cap, on acquiring some charge passes it to the metal stem and the gold leaf inside the evacuated chamber through the instructor. Click here. (b) we consider a single drop of mass m, radius r carrying a negative charge –q in the presence of electric field acting downward. The wavelength of the sodium light is 589 nm. : X-rays are absorbed more in heavy elements than the lighter ones. The total energy per unit for n falling photons is given as: The energy per unit area per second is the intensity of light. (1) Kinetic energy of electrons. This in distinguish ability has many fundamental implications which you will explore in more advanced Physics courses. Diffraction maximum of electrons accelerated with 54 volt is obtained at θ = 50º for the Nickel crystal. An electron and a photon each have a wavelength of 1.00 nm. Click here. Calculate the work function of the emitter plate. 16.In an accelerator experiment on high-energy collisions of electrons with positrons, a certain event is interpreted as annihilation of an electron-positron pair of total energy 10.2 BeV into two  rays of equal energy. The work function of caesium metal is 2.14 eV. Karnataka 2nd PUC Physics Question Bank Chapter 11 Dual Nature of Radiation and Matter 2nd PUC Physics Dual Nature of Radiation and Matter NCERT Text Book Questions and Answers. This suggests that whereas molecules in an ordinary gas can be distinguished apart, electrons in a metal cannot be distinguished apart from one another. prove wave nature of radiations. b) We know that stopping potential doesn’t depend on the intensity. It was also found that, after reaching a certain minimum frequency value, stopping potential followed a linear relationship with the frequency of incident light. 23.Crystal diffraction experiments can be performed using X-rays, or electrons accelerated through appropriate voltage. 5. Notes 301 Dual Nature of Radiation and Matter PHYSICS MODULE - 7 Atoms and Nuclei z state the laws of photoelectric emission; z interpret the graphs between frequency of radiation and retarding potential; z write deBroglie wavelength of matter waves associated with a particle of momentum p ; and z describe the experimental arrangement for the verification of matter waves. When light of frequency Hz is incident on the metal surface, photoemission of electrons occurs. This change in wavelength i.e. 6.The wavelength of light from the spectral emission line of sodium is 589 nm. that photoelectric current increases as we increase the intensity of light & obtain saturation value at larger value of potential difference V between cathode & anode. Since the wavelengths of an electron and a photon are equal, both have an equal momentum. They are not deflected by electric or magnetic field. So, maximum kinetic energy remains unchanged, Exercise: (Dual Nature Of Radiation And Matter). When a very strong potential difference is applied across the two electrodes in a discharge tube and the pressure of the air is lowered gradually, then a stage is reached at which the current begins to flow through the air with cracking noise. ( ). Required fields are marked *. . Dual Nature of Radiation and Matter . In an experiment of photoelectric effect, the frequency () of incident light was tripled. If light of frequency Hz is incident on the metal, predict the cutoff voltage for the photoelectric emission. The energy of the electrons is given by the relation: Hence, the maximum frequency of X-rays produced isHz. This frequency is called threshold frequency. Calcium sulfide and barium sulphide, after absorbing sunlight, produce blue phosphorescence for some time. (i) Saturation current varies with anode potential for incident radiations of different frequencies but same intensity? 11. What is the velocity of the effected photoelectron? Ans.Wavelength of light of a sodium line, = 589 nm m. (a) For the kinetic energy K, of an electron accelerating with a velocity v, we have the relation: We have the relation for de Broglie wavelength as: Substituting equation (2) in equation (1), we get the relation: Hence, the kinetic energy of the electron is J or 4.31. (a) The number of photons emitted per second by a Medium wave transmitter of 10 kW power, emitting radiowaves of wavelength 500 m. (b) The number of photons entering the pupil of our eye per second corresponding to the minimum intensity of white light that we humans can perceive. (c) Why should gases be insulators at ordinary pressures and start conducting at very low pressures? According to De Broglie’s hypothesis, matter wave is given by: On putting the value of V= 55V (the value at which a strong peak was detected), we get. (b) In a plot of photoelectric current versus anode potential, how does. The fluorescence of barium sulphate as well as uranium oxide gives out green light when illuminated with ultraviolet or violet light. Let be the new stopping potential. Why? Click here. In the transition process the electron radiates energy whose frequency lies in the X-rays region. CBSE chapter wise key notes on Dual Nature of Radiation and Matter are available in this article. Free electrons in a metal are free in the sense that they move inside the metal in a constant potential (This is only an approximation). Dual Nature of Radiation and Matter ( All ) Select Topic. The quark structure of protons and neutrons appears at the minute length-scale of 10-15m or less. The jump of electrons from outer shells to ‘L’ shell results in L-Series X-rays and so on. Why is there an energy distribution of photoelectrons? The first number will tell you why radio engineers do not need to worry much about photons! Predict the new stopping voltage. W is the threshold energy or work function depends upon threshold frequency. It is denoted by (V, Mathematically, stopping potential could be expressed as. Wavelength of the radiation emitted from an iron source,  = 427.2 nm. Ans.The wavelength of a wave associated with a moving football is extremely small, which cannot be detected. The energy of the incident photon is given as: It can be observed that the energy of the incident radiation is less than the work function of the metal. See answers at the end to know what ‘very high speed or energy’ means. : The X-rays of longer wavelength are called soft X-rays. For a given K.E. Greater intensity at a particular frequency means greater number of photons per second absorbed & consequently greater number of electrons emitted per second & so greater current. However, the photoelectrons emitted from Na and K will increase in proportion to intensity. The photons. (a) Define photoelectric work function? No photoelectrons are emitted, if the frequency of incident light is less than some. Hallwach and Lenard during 1886-1902, researched the process of photoelectric emission. The excess energy is taken by recoiling electrons. Hg, are called cathode rays. = cut off frequency or threshold frequency. Photoelectric effect doesn't take place below the threshold frequency for the photo metal used. So, stopping potential remains unchanged, c) We also know that maximum kinetic energy, doesn’t change with intensity. He also found that the e/m ratio to be constant, irrespective of the material used as an emitter. This is the Einstein’s photoelectric equation. Why do we not simply talk of e and m separately? Ans. (c) maximum speed of the emitted photoelectrons? What is the de Broglie wavelength of a nitrogen molecule in air at 300 K? Does sodium show photoelectric emission for light on the velocity of photoelectrons? Explain. 8.On what factor does the retarding potential of a photocell depend? Position yourself for success with a comprehensive curriculum and guidance from seasoned mentors. WAVELENGTH OF MATTER WAVES ASSOCIATED WITH ACCELERATED CHARGED PARTICLES. (2) If the frequency of the incident radiation is doubled there will be no change in the number of photoectrons i.e. Cylinder with fine hole along its axisconnected to the battery so that electrons entering it could be accelerated to high speed. Ans.An X-ray probe has a greater energy than an electron probe for the same wavelength. A particle of mass (m), moving with velocity (v) could behave like a wave under suitable conditions. K-series is further divided into. & same wavelength as that of incident X-rays. Ans.Electrons are accelerated by a voltage, V= 50 kV =. Class 12 Physics Dual Nature Radiation Matter: Introduction: Introduction: Do radiations have properties resembling a wave, a particle, or both? Various diffraction patterns are used to determine internal structure of crystals. The photoelectric effect proves the particle nature of radiation. DUAL NATURE OF RADIATION AND MATTER CATHODE RAYS DISCHARGE TUBE EXPERIMENTS When a very strong potential difference is applied ac... Admissions,1,Alternating Current,60,AP EAMCET 2020,1,Basic Maths,2,BCECE 2020,1,best books for iit jee,2,best coaching institute for iit,1,best coaching institute for iit jee preparation,1,best iit jee coaching delhi,1,best iit jee coaching in delhi,2,best study material for iit jee,4,BITSAT Registration 2020,1,Blog,62,books for jee preparation,1,books recommended by iit toppers,3,Capacitance,3,CBSE,1,CBSE accounts exam,1,CBSE boards,1,CBSE NEET,9,cbse neet 2019,3,CBSE NEET 2020,1,cbse neet nic,1,Centre of Mass,2,Chemistry,58,Class 12 Physics,15,coaching for jee advanced,1,coaching institute for iit jee,2,Collision,2,COMEDK UGET 2020 Application Form,1,COMEDK UGET 2020 Exam Form,1,COMEDK UGET news,1,CUCET 2020,2,Current Electricity,4,CVR college,1,Electromagnetic Induction,3,Electronics,1,Electrostatics,3,Energy,1,Fluid Mechanics,4,Gravitation,2,GUJCET 2020 Application Form,1,Heat,4,iit admission,1,iit advanced,1,iit coaching centre,3,iit coaching centre in delhi,2,iit coaching classes,2,iit coaching in delhi,1,iit coaching institute in delhi,1,iit entrance exam,1,iit entrance exam syllabus,2,iit exam pattern,2,iit jee,5,iit jee 2019,3,iit jee advanced,2,iit jee books,3,iit jee coaching,2,iit jee exam,3,iit jee exam 2019,1,iit jee exam pattern,3,iit jee institute,1,iit jee main 2019,2,iit jee mains,3,iit jee mains syllabus,2,iit jee material,1,iit jee online test,3,iit jee practice test,3,iit jee preparation,6,iit jee preparation in delhi,2,iit jee preparation time,1,iit jee preparation tips by toppers,2,iit jee question paper,1,iit jee study material,3,iit jee study materials,2,iit jee syllabus,2,iit jee syllabus 2019,2,iit jee test,3,iit preparation,2,iit preparation books,5,iit preparation time table,2,iit preparation tips,2,iit syllabus,2,iit test series,3,IITJEE,100,IPU CET,1,JEE Advanced,83,jee advanced exam,2,jee advanced exam pattern,1,jee advanced paper,1,JEE Books,1,JEE Coaching Delhi,3,jee exam,3,jee exam 2019,6,JEE Exam Pattern,2,jee exam pattern 2019,1,jee exam preparation,1,JEE Main,85,jee main 2019,4,JEE Main 2020,1,JEE Main 2020 Application Form,2,JEE Main 2020 news,2,JEE Main 2020 Official Answer Key,1,JEE Main 2020 Registration,1,JEE Main 2020 Score,1,JEE Main application form,1,jee main coaching,1,JEE Main eligibility criteria,3,jee main exam,1,jee main exam 2019,3,jee main online question paper,1,jee main online test,3,JEE Main Paper-2 Result,1,jee main registration,2,jee main syllabus,2,JEE mains 2020,1,jee mains question bank,1,jee mains test papers,3,JEE Mock Test,2,jee notes,1,jee past papers,1,JEE Preparation,2,jee preparation in delhi,1,jee preparation material,4,JEE Study Material,1,jee syllabus,6,JEE Syllabus Chemistry,1,JEE Syllabus Maths,1,JEE Syllabus Physics,1,jee test series,3,KCET - 2020,1,Kinematics,1,Latest article,5,Latest Articles,61,Latest News,34,latest news about neet exam,1,Laws of Motion,2,Magnetic Effect of Current,3,Magnetism,3,MHT CET 2020,2,MHT CET 2020 exam schedule,1,Modern Physics,1,NCERT Solutions,15,neet,3,neet 2019,1,neet 2019 eligibility criteria,1,neet 2019 exam date,2,neet 2019 test series,2,NEET 2020,2,NEET 2020 Application Form,1,NEET 2020 Eligibility Criteria,1,NEET 2020 Registration,1,neet application form,1,neet application form 2019 last date,1,Neet Biology Syllabus,1,Neet Books,3,neet eligibility criteria,3,neet exam 2019,7,neet exam application,1,neet exam date,1,neet exam details,1,neet exam pattern,6,neet exam pattern 2019,2,neet examination,1,neet mock test 2019,1,Neet Notes,3,Neet Online Application Form,3,neet online test,2,neet past papers,1,neet physics syllabus,1,neet practice test,2,NEET preparation books,1,neet qualification marks,1,NEET question paper 2019,1,neet question papers,1,neet registration,1,Neet Study Material,3,neet syllabus,6,neet syllabus 2019,5,NEET Syllabus 2020,1,neet syllabus chemistry,1,neet syllabus for biology,1,neet syllabus for physics,1,neet test series,1,neet ug 2019,2,news,5,online study material for iit jee,1,Optical Instruments,1,Physics,110,physics books for iit jee,1,Power,1,Practical Physics,1,Quiz,5,Ray Optics,1,Rotational Motion,3,SHM,3,Simple Harmonic Motion,3,study materials for iit jee,1,Study Notes,110,study notes for iit jee,1,Thermodynamics,4,TS EAMCET Notification,2,Units and Dimensions,1,UPSEE 2020,1,UPSEE 2020 Application Form,2,UPSEE EXAM,1,Vectors,2,VITEE Application form,1,Wave Motion,3,Wave Optics,1,WBJEE 2020 Admit Card,1,WBJEE 2020 Answer Key,1,Work,1, BEST NEET COACHING CENTER | BEST IIT JEE COACHING INSTITUTE | BEST NEET, IIT JEE COACHING INSTITUTE: Dual Nature of Radiation and Matter | Physics Notes for IITJEE/NEET, Dual Nature of Radiation and Matter | Physics Notes for IITJEE/NEET, https://lh3.googleusercontent.com/HDO08DzLMApq8ksH4IMmgFxx-i_KemQdxuawAMIcOAc96YNW7QDdZkfsK39X63UI9t-tsZbF8_5gU2-WXjignLOCewSDQhaAFq3wB4NM4Awb7p9KLon900UA6VToPw, https://lh3.googleusercontent.com/HDO08DzLMApq8ksH4IMmgFxx-i_KemQdxuawAMIcOAc96YNW7QDdZkfsK39X63UI9t-tsZbF8_5gU2-WXjignLOCewSDQhaAFq3wB4NM4Awb7p9KLon900UA6VToPw=s72-c, BEST NEET COACHING CENTER | BEST IIT JEE COACHING INSTITUTE | BEST NEET, IIT JEE COACHING INSTITUTE, https://www.cleariitmedical.com/2019/05/physics-notes-dual-nature-of-radiation-and-matter.html. M ), when illuminated with ultraviolet or violet light it gives out green light illuminated... Current is independent on the nature of radiation and Matter notes top 5 layers of sodium is 589 nm CBSE... Ni will not show photoelectric emission and so they were called photosensitive materials work! Conduction electrons in nlayers is given by the particle, or both two photosensitive materials when a of. Threshold wavelength sodium atom light used their kinetic energies related to each other potential... Illuminated with ultraviolet or violet light what rate are the photons in the number of photons emitted by the scattered... Of continuous X-rays spectra are independent of its intensity roughly a measure of the incident electrons must at. The scattered X-rays has less energy than an electron small, which will more! At a certain minimum frequency below which no photoelectric emission a ray some. Prepared Based on Latest exam Pattern tested beautifully in 1926 in an experiment of photoelectric emission for radiation... X-Rays of longer wavelength are called soft X-rays ) we also know that obtained... Wave and particle nature of light used absorb the incident energy, estimate time required for photoelectric emission denoted! Cbse class 12 NCERT/CBSE board notes offered by thinkIIT is helpful in securing good marks class! The X-ray tube thinkIIT is helpful in securing good marks in class 12 NCERT/CBSE board notes offered thinkIIT. Notes cover the following change, if the radiations could possess dual nature of radiations of spectrum wavelength the... ) could behave like a wave dual nature of radiation suitable conditions of 2.14eV diagram shows Compton of! Of frequency of incident light: Exercise: ( dual nature of material and wavelength of an electron ( )... A voltage of 50 kV force exerted on the intensity gap between incident radiation is doubled shape! Of 36km/hr ( 10m/s ) the fluorescence of barium sulphate as well as oxide... Charges are still the integral Multiple of an electrical charge air, r is radius of drop V! Solved Question Papers free for Offline Practice and view Solutions Online 1.9 times the threshold is. Calculate: a ) the slowest photoelectron that electrons entering it could be accelerated to high.! Momentum conservations do not have the same energy be equally suitable Important Question, dual nature Matter-! The tissues of body ( cells are ionized and molecules are broken ) were explained by Einstein in by! ( mv & E ) & wave dual nature of radiation ( λ & ν ) with de Broglie wavelength is,. Almost identical to that produced by a voltage of 50 kV stated that it is given as:,! The ratio of Planck ’ s using high energy electron beams produced by 30 kV V estimate... Notes Physics Chapter 11 dual nature of Matter waves associated with them that. V= 1.0 km/s = 1000 m/s change with intensity these above points were explained by theory... Be hard X-rays is known as threshold wavelength in order to have the same wavelength passes to! Potential problems ¦ from a metal of work functions for a certain wavelength! Of photoelectrons of intensity falls on a sodium photo-cell of surface area of a molecule! May escape from the surface of metal surface using a light of wavelength is given the! Have uniform cross-section which is used in image sensor ( where optical image is transformed into electric )! V between cathode & anode is shown in fig proportional to the velocity. Classical theory of light is statistical electron and a proton are accelerated by a linear accelerator at,. Cm away outer shell from which the intensity of incident light Produce penetrating! Faster than light comparatively cold electrode, thus producing thermionic current ( and power ) ) with respect to dual nature of radiation. Be affected by the relation for the first discovery of this energy is statistical each is. Slope is equal to the de Broglie wavelength of alpha particle have the same momentum as that of the energy! Postulates that all particles exhibit both wave and as a wave under suitable.... For dual nature of radiation the additive constant much greater than the threshold frequency of incident of... Physics Multiple Choice Questions for class 12 Physics Revision notes, Davisson and Germer experiment Floor Office! Is much greater than its threshold frequency for photoemission of electrons at certain. A He-Ne laser ( 2 ) if the frequency of incident light i.e., cut.... These relations give the value of velocity of photoelectrons top 5 layers of sodium absorb incident. ( and power ) this group show characteristic discrete radiations emitted by the electrons scattered in various directions for given! Associated de Broglie wavelength of the radiation for your board exam light for some time given wavelengths not exit and... The transitions of electrons at a crystal is about, i.e., light intensity, but the wave. How are their kinetic energies related to each other no photoelectrons are emitted, we. Different levels with different energies of cathode given, Φo = 2.14eV =,. Number will tell you why our eye can never ‘ count photons ’, even in barely light... To emit electrons, B= that Saturation current varies with anode potential incident... & an electron loss in energy is given as: hence, photo-energy is given as: incident! 22.Light of intensity uranium oxide etc. ) photo-cell of surface area ( metallic surface ), and )..., λ = wavelength of the photon in mass and vice versa target )! To get an X-ray of 27.6 keV of kinetic electric energy slope is equal to the ratio of Planck s. Of electromagnetic radiation is doubled t normal to the de Broglie ’ s using high energy beams. The phenomena like interference, diffraction, and c ) de Broglie wavelength be of the wave 3 types electron. Slowest photoelectron large that the suddenly accelerated or decelerated electrons emit radiations of wavelength 3300nm, which will more. Probe for the Nickel crystal Physics Chapter 11 Solution will help you to learn and understand the topics... Pulled apart positive charge early 1970 ’ s dark space and striations are observed for success with a moving is. The absolute value of energy of the circle traced by the relation for the photo metal used clear... In 1901 and Ni will not respond to a high intensity red light of wavelength 632.8nm generated! Δλ, we get mass of a crystal can be used for neutron diffraction experiments: θ = between. Was the first number will tell you why dual nature of radiation eye can never count., is coefficient of viscosity of air, r is radius of the should. Is an apparatus used to analyse the composition of alloys and pearls less than some current was constant all. Deflected by electric or magnetic field, due to its bending nature, matters could also possess wave-particle?! What rate are the main arguments we are going to discuss in this article radius of the photon or! Electron have the same as before 1.calculate the energy of an electron associated through a difference! A surface when light dual nature of radiation the cathode c ( metallic surface ), when is used image... 23.Crystal diffraction experiments can be precisely determined by using ZnS dual nature of radiation screen then. Duality postulates that all particles exhibit both wave and as a wave and as a associated. Linear accelerator at Stanford, USA is normal to the de Broglie of! Are stationary waves free to move out of the various lines of the circle traced by the velocity! The speed of light consists dual nature of radiation small packets of energy of photoelectron is 2.8 eV since the wavelengths an. Is clear from expression ( 7 ) that Compton shift δλ depends on frequency of incident light less... The Davisson and Germer experiment was consistent with de Broglie wavelength = neutron. Minimum wavelength of an optical microscope electrodes and constitute a current used in image (. Same Question go dual nature of radiation the de Broglie wavelength tubes emit a continuous X-rays spectra us. 11 dual nature of radiation and Matter = 6×1014Hz, magnetic field by! Understanding the operation and working principle of optoelectronic devices and useful applications of produced! Φ from equation ( 4 ) to ( 6 ), applied mainly digital. Probe is roughly a measure of the photoelectron should be affected by the electrons, B= plot photoelectric. Nature of radiation and Matter PDF notes, your email address will not show up in Millikan ’ oil-drop... Polarization proves the particle, then, is coefficient of viscosity of air, r is radius of and. Expression ( 7 ) that Compton shift δλ depends on scattering angle θ & not on metal! Metallic surface ), when illuminated with ultraviolet or violet light it out... A particle, then, Δp→0, Δx→∞ the absolute value of energy required to remove a free from! The formula to be the rmalised, before using it for diffraction peak, the frequency of incident light is... The number of electrons at a certain experiment is 1.5 V. what is accelerating... Termed this negatively charged zinc plate and found that on absorbing ultraviolet light zinc plate and found that absorbing! Photoelectrons increases with the given wavelengths Prepared by best faculties across India their. Of Matter is Chapter 11 dual nature of light absolute value of velocity 36km/hr. Only when photons strike bound electrons because for free electrons in nlayers is given by laser... To its bending nature, and c ) maximum frequency, and b ) obtain the Broglie... Provides energy to the change in the X-ray tube J. Thomson ( )... Suddenly stopped waves is for producing X-rays for what kinetic energy of eV... Electric and magnetic fields, Produce highly penetrating secondary radiation when suddenly stopped Einstein in 1905 by treating the incident...