Three experiments arqq/f)lg*e5i o ,w ev*be listed.

I. Photoelectric effect

II. Davisson-Germer experiment

III. Young’s double-slit experiment

Which of the experiments show the existence of the wave behavior of matter?

  In a vacuum chamber, n,zsywu cg8,i36t7 lp electromagnetic radiation of frequencies $f_A$​<$f_B$​ just manage to produce a non-zero photocurrent from metals A and B respectively. When illuminated by an electromagnetic radiation of frequency $f$>$f_B$​, the stopping voltage for the photocurrents from plates A and B are recorded to be $V_A$​ and $V_B$​ respectively.
Which of the following is true about $V_A$​ and $V_B$​?

  Two lasers, A and B emit light of the same wavelength. If the intensity of A is greater than that of B, which of the following statements would be the correct interpretations of this situation using the wave and particle models of light.

  The graph below shows the graph of the maximum kineticu fax, aziffju2 :pl159xz0g.k6gh3 l energy ($E_k$​)of the emitted electrons against incident frequency ($f$) plotted by a student investigating the work function for a particular metal.

Which of the following can be used by the student to get an approximate value for the work function of the metal in question?

  Light from a sodium lamp of wavelength is direct)d ievfiqv 5;;/ lg z-1kdn:ql.n. kxzed towards a metal surface and electrons untiqn del d nx 1lzfz;i)q:gvk5k.v/;.-il a stopping potential of $V_s$​ is applied. The wavelength of the incident light is halved. Which of the following corresponds to the new value of the required stopping potential?

  No electrons are emitted-kb 63s g:tkz4 +q-nfs,f wykf when metal plate X is irradiated by an electromagnetic radiayfwfkb f ks-+zg:-sq6,n 3t4ktion of wavelength λ, and intensity I. Which of the following could result in emission of photoelectrons?

I. Decreasing the wavelength λ of incident light.

II. Increasing the intensity of electromagnetic radiation at the same wavelength.

III. Replacing metal X, with a metal of smaller threshold frequency.

  1.Light falls on a p+mble.po,3onl,hld + d*c p;jhotoelectric surface with a threshold frequency of $5.2\times10^{14}\,Hz$.

State what is meant by photoelectric emission.
2.(1)Calculate the work function of the photoelectric surface in electronvolts. $ϕ$ =    $eV$
(2)The ammeter gives a reading when a violet light is used, while it reads zero when a red light with the same intensity is used. Explain this observation.
(3)The frequency of violet photons is $7.5\times10^{14}\,Hz$. Calculate the maximum speed of the emitted electrons.
3.On the axes below, sketch the variation of the photoelectric current with the potential difference for an incident frequency above the threshold frequency. Also label the stopping voltage $V_s$​. v =    $\times10^5\,ms^{-1}$

  1.A beam of electrons is inck)xkni s5e0s:l k.2fyident on an iron foil (Z=56) and electrons are diffracys :ek. iklsxn5fk 0)2ted. In the experiment, electrons have initial kinetic energy of 42 GeV. The first diffraction minimum is observed at an angle of $49^{\circ}C$ from the average position of most of the electrons detected.

(1)Calculate the density of the iron nucleus. $ρ$ =    $\times10^{17}\,kgm^{-3}$
(2)Using the diffraction information​ given, estimate the radius $r$ of the iron nucleus . r =    $\times10^{-15}\,m$
2.In another experiment, alpha particles are emitted towards iron foil with an initial kinetic energy of $125\,ke\,V$. Estimate the distance of the closest approach to the iron nucleus of the alpha particles. r =    $\times10^{-14}\,m$

  The photocurrents produced by illuminating a metal plate withpf(y0a. ybj;d 4tz:pi. a7ig q yellow light beams jazdy7 ;t4(fq0 .pb:.agpi yi of intensities $I_1$​ and $I_2$​ are $i_1$​ and $i_2$​ respectively. The corresponding stopping voltages are $V_1$​ and $V_2$​. Given that $I_1$​<$I_2$​ , which of the following statements is true about the photocurrents and the stopping voltages?

  1.De Broglie related the wavelength of a parss3 ;;no kpz3c 9-yrmsticle to its momentum. State what is meant by mattkmz -3;srn o 93p;sscyer waves.
2.(1)Show that the wavelength $λ$ of an electron of mass $m$ and kinetic energy $E$ can be found from
λ = $\frac{h}{\sqrt{2mE}}$
(2)Assuming that the magnitude of the energy of a given energy level of an atom is equal to the kinetic energy of the electron, show that the wavelength of the electron in the second energy level in a hydrogen atom is approximately $6.7\times10^{−10}\,m$. $λ$ =    $\times10^{-10}\,m$
(3)Use the wavelength from b(ii) to estimate the orbital radius of this electron. r =    $\times10^{-10}\,m$

  RRed and blue light beams of equal intensities illuminate a ph p w61skib .biuj*2pq qzbqrj:6:b27dotosensitive plate and produce photocurre12q pz u 7.:6spb:2qd6wbbkq jr*i ijbnts $I_R$​ and $I_B$​ respectively. The respective stopping voltages against the two photocurrents are $V_R$​ and $V_B$​.
Consider the following statements:
I. $I_R$​>$I_B$​
II. $V_R$​<$V_B$​
III. Photoelectrons with higher kinetic energy result in a higher current.
Which statements are correct?

  In a laboratory experinie g; 0ov0l 0q.8kada d:jx2bfr 9xl/ment, $n$ moles of photons of wavelength $λ$ are normally incident every second per square meter on a solar sail. Which of the following expressions correctly states the photo-pressure on the solar sail, given that the photons are reflected elastically.

  Two photosensitive plates A and B1 a on9bnoo3noh0l o,8;hau2m with threshold frequencies $f_A$​ and $f_B$​ are illuminated in a vacuum with an electromagnetic radiation of wavelength λ such that photoelectrons are emitted from both plates. The corresponding stopping voltages are recorded to be $V_A$​ and $V_B$​ respectively.
The ratio $\frac{V_B-V_A}{f_A​-f_B}$