Which of the following correctly states the conclusion drawn from the Rutherford-Geiger-Marsden experiment?

  

  An electron in a hydrogenqs6x84j )aq yy atom is excited from the ground state of $n=1$ to the $n=4$ level. What is the total number of frequencies that can be observed from the emission spectrum as the electron returns to ground state?

  A student investigates the scattering of alpha particl17dkj1 tukn opp+248 /9oskkqq)vvm hes. Initially, she uses a gold foil (Z = 79) and next she repeats the experiment using an aluminum (Z = 13) foil of the same thickness. The scattered alpha particles are observed on a detecto 12qpkn1dk)mpuj +okv9h8t/4ksq v7or that fluoresces.
Which of the following will be true as she switches from the gold foil to the aluminum foil?
I. The alpha particles deflect more from the gold nucleus than the aluminum.
II. The alpha particles approach the gold nucleus closer than the aluminum nucleus.
III. There is no change in the observed scattering pattern.

  The diagram shows atomic energy levels of an element, and wavelengths are labeled corresponding to emission for electron transition between certain energy levels.


Which of the following shows these wavelengths in decreasing order?

  1.With reference to energy conversion, distinguish between photovoltaic celld2p)p4- fmvjh s and solar heating panjp4pd 2)f -hmvels.
2.On a sunny day, a house is powered by a solar panel. In order to run home appliances, the incident power of sunlight on the solar panel must be 10 kW.
(1)The average surface temperature of the Sun is 5850K. Show that the peak wavelength of the emission of the sun is around 500nm. $λ_max$ =    nm
(2)It can be assumed that 7.5% of the energy from incident sunlight consists of peak wavelength photons that are converted to electrical energy by the panel. Calculate the number of 500nm photons that must strike the solar panel per second in order to meet the power requirement of the appliances. n =    $\times10^{21}$

  The nucleon numbers of elements X and Y are A and 8A respectively. Theiu 8x c;cx0su3er radii arexucue 8sc ;x03 $R_X$​ and $R_Y$​, and their densities are $ρ_X$​ and $ρ_Y$​.
Which of the following shows the correct values of the ratios $\frac{R_Y}{R_X}$ and $\frac{ρ_X}{ρ_Y}$​​?

  Which value below gives the closest approximation for the diameter of a uranium-238 nucleus?

  The electron in the ground state of a hydrogen atom absorbs a certain amouy 86wx,7j iw*4hy;pm l9 zln;l;vzsxg nt of energy. The diagram shows some of the energy levels of the hydrogen atom. At which state would the elect6;v9zi;l 4 pxjlgynww*sx7z, y;hm l 8ron be if it absorbs 12.09 eV of energy?

  The diagram shows six energy levels of hydrogen.



1.Describe how an emission spectrum is an evidence of discrete energy levels in an atom.
2.(1)On the energy level diagram, draw an arrow to represent the transition that emits the shortest wavelength.
(2)Calculate the shortest emitted wavelength. λ =    m $\times10^{-8}$
3.Emitted red light has a frequency estimation of 460 THz. Determine which energy level transition emits this red light. E =    eV

  Alpha particles of kinetic ecbk,/iqr( g k5nergy K are fired at nuclei of proton number Z.
The number of particles scattered at different angles are in agreement with the prediction of Rutherford's scattering model.
Which of the following changes to the values of K and Z will result in a significant deviation from Rutherford's model?

  The nuclear energy levels of a nucleus are shown below. K, L, and M are transitions between energy levels.


Which statements are correct about photons emitted during transitions K, L, and M?
I. The wavelength of the photon emitted by transition K is greater than the wavelength of the photon emitted by transition L.
II. The frequency of the photon emitted by transition K is equal to the frequency of the photon emitted by transition M.
III. The wavelength of the photon emitted by transition L is greater than the wavelength of the photon emitted by transition M.

  A thorium-234 (Th-234) nucleus undergoesp jimyq039( lefo4ca 1 beta decay and transforms into a protactinium-234 nucleus (Pa-234). The binding energies per nucleon f3 (iy0faomqc1el9 4 jpor Thorium-234 and protactinium-234 are 7.84 MeV and 7.92 MeV respectively. An electron has a rest mass energy of 0.020 MeV.
The reaction can be represented as follows:
$^{234}_{90}Th→^{234}_{91}Pa+10e^{-}+\overline{v_e}$
(1)Explain what is meant by binding energy per nucleon.
(2)Calculate, in joules, the total energy released in the decay. The total energy released in Joules:    $\times10^{-12}\,J$


2.A cubic container is filled with pure thorium-234. The container does not contain any other elements. After 62 days, the ratio of the number of nuclei of decay product to thorium-234 nuclei is 5.
Calculate, in days, the half-life of the thorium-234 nuclei. $t_{\frac{1}{2}}$ =    days

  Some of the energy levels of electrons of a mercury atom are as shown.



Electrons and photons are incident on a mercury vapour causing energy level transitions. Emitted photons due to the transition of electrons between energy levels from the vapour have an energy of 4.9 eV.
Which of the following could be incident into mercury vapour?

I. An electron with an energy of 5.1 eV
II. A photon with an energy of 4.9 eV
III. A photon with an energy of 5.1 eV

  The diagram gives energy levels of a single-electron atom.


How many different wavelengths can be detected in the emission spectrum of the atom?