User interface language: English | Español

HL Paper 1

What is the charge on an electron antineutrino and during what process is an electron antineutrino produced?




Which of the following lists the particles emitted during radioactive decay in order of increasing ionizing power? 

A. γ, β, α
B. β, α, γ
C. α, γ, β
D. α, β, γ




The mass of nuclear fuel in a nuclear reactor decreases at the rate of 8mg every hour. The overall reaction process has an efficiency of 50%. What is the maximum power output of the reactor?

A.  100MW

B.  200MW

C.  100GW

D.  200GW




A pure sample of nuclide A and a pure sample of nuclide B have the same activity at time t = 0. Nuclide A has a half-life of T, nuclide B has a half-life of 2T.

What is  activity of A activity of B when t = 4T?

A.  4

B.  2

C.   1 2

D.   1 4




Which Feynman diagram describes the annihilation of an electron and its antiparticle?




A detector measures the count rate from a sample of a radioactive nuclide. The graph shows the variation with time of the count rate.

The nuclide has a half-life of 20 s. The average background count rate is constant.

What is the average background count rate?


A.  1 s−1

B.  2 s−1

C.  3 s−1

D.  4 s−1




Which is the correct Feynman diagram for pair annihilation and pair production?

 




The Feynman diagram shows an interaction between a proton and an electron.

What is the charge of the exchange particle and what is the lepton number of particle X?





In the Rutherford-Geiger-Marsden scattering experiment it was observed that a small percentage of alpha particles are deflected through large angles.

Three features of the atom are

I.   the nucleus is positively charged

II.  the nucleus contains neutrons

III. the nucleus is much smaller than the atom.

Which features can be inferred from the observation?

 

A.   I and II only

B.   I and III only

C.   II and III only

D.   I, II and III




A radioactive nuclide X decays into a nuclide Y. The graph shows the variation with time of the activity of X. X and Y have the same nucleon number.

What is true about nuclide X?

A.  alpha (α) emitter with a half-life of t

B.  alpha (α) emitter with a half-life of 2t

C.  beta-minus (β) emitter with a half-life of t

D.  beta-minus (β) emitter with a half-life of 2t




The carbon isotope 14 6 C is radioactive. It decays according to the equation

14 6 C →  14 7 N + X + Y

 

What are X and Y?




A pure sample of iodine-131 decays into xenon with a half-life of 8 days.

What is number of iodine atoms remainingnumber of xenon atoms formed after 24 days?

A.  18

B.  17

C.  78

D.  87




A neutron is absorbed by a nucleus of uranium-235U92235. One possible outcome is the production of two nuclides, barium-144Ba56144 and krypton-89Kr3689.

How many neutrons are released in this reaction?

A.  0

B.  1

C.  2

D.  3




The diagram shows atomic transitions E1, E2 and E3 when a particular atom changes its energy state. The wavelengths of the photons that correspond to these transitions are λ1, λ2 and λ3.

What is correct for these wavelengths?

A.  λ1>λ2>λ3

B.  λ1=λ2+λ3

C.  1λ1=1λ2+λ3

D.  1λ1=1λ2+1λ3




In a hydrogen atom, the sum of the masses of a proton and of an electron is larger than the mass of the atom. Which interaction is mainly responsible for this difference?

A. Electromagnetic

B. Strong nuclear

C. Weak nuclear

D. Gravitational




The  π + meson contains an up ( u ) quark. What is the quark structure of the  π meson?

A. u d

B.  u d ¯

C.  u ¯ d

D. u ¯ d ¯




Nuclide X can decay by two routes. In Route 1 alpha (α) decay is followed by beta-minus (β) decay. In Route 2 β decay is followed by α decay. P and R are the intermediate products and Q and S are the final products.

Which statement is correct?

 

A.  Q and S are different isotopes of the same element.

B.  The mass numbers of X and R are the same.

C.  The atomic numbers of P and R are the same.

D.  X and R are different isotopes of the same element.




The following decay is observed.

μ → e + vμ + X

What is particle X?

 

A.   γ

B.    v ¯ e

C.   Z0

D.   ve




Carbon (C-12) and hydrogen (H-1) undergo nuclear fusion to form nitrogen.

C+612H →N+11 photon

What is the number of neutrons and number of nucleons in the nitrogen nuclide?




White light is emitted from a hot filament. The light passes through hydrogen gas at low pressure and then through a diffraction grating onto a screen. A pattern of lines against a background appears on the screen.

What is the appearance of the lines and background on the screen?




The diagram shows the emission spectrum of an atom.

Which of the following atomic energy level models can produce this spectrum?




What is correct about the Higgs Boson?

A.     It was predicted before it was observed.

B.     It was difficult to detect because it is charged.

C.     It is not part of the Standard Model.

D.     It was difficult to detect because it has no mass.




Gamma (γ) radiation

A.  is deflected by a magnetic field.

B.  affects a photographic plate.

C.  originates in the electron cloud outside a nucleus.

D.  is deflected by an electric field.




Identify the conservation law violated in the proposed reaction.

                                                 p+ + p+ → p+ + n0 + μ+

A.     Strangeness

B.     Lepton number

C.     Charge

D.     Baryon number




In the nuclear reaction X + Y → Z + W, involving nuclides X, Y, Z and W, energy is released. Which is correct about the masses (M) and the binding energies (BE) of the nuclides?




Which of the following leads to a paradigm shift?

A. Multi-loop circuits

B. Standing waves

C. Total internal reflection

D. Atomic spectra




During the nuclear fission of nucleus X into nucleus Y and nucleus Z, energy is released. The binding energies per nucleon of X, Y and Z are BX , BY and BZ respectively. What is true about the binding energy per nucleon of X, Y and Z?


A.  BY > BX and BZ > BX

B.  BX = BY and BX = BZ

C.  BX > BY and BX > BZ

D.  BX = BY + BZ




A sample of a pure radioactive nuclide initially contains N0 atoms. The initial activity of the sample is A0.

A second sample of the same nuclide initially contains 2N0 atoms.

What is the activity of the second sample after three half lives?

A.  A02

B.  A04

C.  A06

D.  A08