Verified past-paper data not yet uploaded
No verified paper has been uploaded for AJKPSC-PMS Paper Physics 2001 MCQs yet.
The MCQs below are drawn from the Physics subject category.
Showing 1701–1710
of 15721 MCQs
Page 171 / 1573
1701
The constituants of atomic nuclei are believed to be
A. electrons and protons
B. electrons, protons and neutrons
C. neutrons and protons
D. protons only
Discuss
Save
Correct Option
Explanation
As indicated by the provided answer key, option C ('electrons and protons') is marked as the correct choice in the block metadata.
1702
A nucleus with mass number 220 initially at rest emits an α-particle. If the Q value of the reaction is 5.5 MeV, calculate the kinetic energy of the α-particle.
A. 6.5 MeV
B. 5.6 MeV
C. 4.4 MeV
D. 5.4 MeV
Discuss
Save
Correct Option
Explanation
Correct option taken from the block's answer hint (A) as provided in the header.
1703
The wavelength of X-rays is of the order of
A. 10^-14 m
B. 10^-6 m
C. 10^-8 m
D. 10^-10 m
Discuss
Save
Correct Option
Explanation
Typical X-ray wavelengths are around 10^-10 meters (angstrom scale).
1704
Uncertainty principle was stated by:
A. Dirac
B. Anderson
C. Heisenberg
D. de Broglie
Discuss
Save
Correct Option
Explanation
Werner Heisenberg formulated the uncertainty principle in 1927, so option C is correct.
1705
Among the three types of radioactive radiation, which has the strongest penetration power?
A. Gamma
B. All have same penetration power
C. Alpha
D. Beta
Discuss
Save
Correct Option
Explanation
Gamma rays have the highest penetration among alpha, beta, and gamma; the OCR shows a marker adjacent to option B.
1706
The wavelength of X-rays decreases, when
A. intensity of electron beam is increased
B. temperature of target is increased
C. kinetic energy of electrons striking the target is increased
D. kinetic energy of electrons striking the target is decreased
Discuss
Save
Correct Option
Explanation
Higher kinetic energy of incident electrons produces higher energy (shorter wavelength) X-rays, reducing wavelength.
1707
The binding energy per nucleon for uranium is about
A. 21.6 MeV
B. 7.7 MeV
C. 13.6 MeV
D. 9.6 MeV
Discuss
Save
Correct Option
Explanation
The binding energy per nucleon for heavy nuclei like uranium is around 7–8 MeV, so 7.7 MeV is correct.
1708
During a beta (β) decay how do the atomic number and mass number of a nucleus change?
A. Atomic number increases by one; mass number decreases by two
B. Atomic number increases by one; mass number remains the same
C. Atomic number decreases by two; mass number decreases by four
D. Atomic number remains the same; mass number increases by one
Discuss
Save
Correct Option
Explanation
In β− decay a neutron converts to a proton and an electron, so atomic number increases by one while mass number remains unchanged.
1709
Compton's effect was presented in
A. 1933
B. 1923
C. 1931
D. 1921
Discuss
Save
Correct Option
Explanation
Arthur H. Compton presented the Compton effect in 1923, so the 1923 option is correct.
1710
The energy of a hydrogen atom in its ground state is -13.6 eV. The energy corresponding to first excited state is
A. -1.51 eV
B. +3.4 eV
C. -3.4 eV
D. -10.2 eV
Discuss
Save
Correct Option
Explanation
Energy of level n is -13.6/n^2 eV; for n = 2 this gives -13.6/4 = -3.4 eV, so option A is correct.
