51- What is the processes involved in. the atom bomb
(A) Nuclear ionization
(B) Nuclear fission
(C) Nuclear Fusion
(D) Nuclear enrich
52- The minimum energy needed to pull a free electron on the surface of a metal is called
(A) Kinetic energy
(B) Work function
(C) Potential energy
(D) Critical potential
53- When a radioactive nucleus emits α particle its atomic number and mass number
(A) Both decreases by 3
(B) Increases by 2 decreases by 4 respectively
(C) Do not change
(D) Decreases by 2 and decreases by 4 respectively
54- The energy of an electron in. an atom is
(A) Greater in inner orbits them in outer orbits
(B) Greater in outer orbits them in inner orbits
(C) Depending on the atom
(D) Always same irrespective of orbits
55- If the number of protons or neutrons in a nucleus is equal to ___ it is called a magic number
(A) 100
(B) 105
(C) 116
(D) 126
56- Millikan’s experiment is used to calculate
(A) electronic mass
(B) e/m ratio
(C) electronic charge
(D) electronic size
57- Which one of the following series of hydrogen spectral lines occurs in the ultra violet region?
(A) Balmer series
(B) Lyman series
(C) Bracket series
(D) Pfund series
58- The possible values of magnetic quantum number for each ‘l’ are given by
(A) 2l-1
(B) 2l+1
(C) l-1
(D) l+1
59- When the light source is placed in a magnetic field, the spectral lines are split into two or three lines is called
(A) Normal Zeemen effect
(B) Anomalous Zeeman effect
(C) Paschen – back effect
(D) Photo electric effect
60- Aston’s mass spectrograph is used to identify various ___ of an element.
(A) isotopes
(B) charges
(C) structures
(D) spectral lines
ANSWERS:
51-(B), 52-(B), 53-(D), 54-(B), 55-(D), 56-(C), 57-(B), 58-(B), 59-(A), 60-(A)