Quantum physics describes the fundamental theory of particles at atomic and subatomic levels. It underlines the understanding of matter at the scale of atoms and sub-atoms. It deals in the study of physical phenomena at microscopic level taking into account the dual behaviour of matter. In the realm of the universe, quantum physics explains how all the particles in nature interact with matters in existence.
Question 1: ______________ waves can be transmitted through solid, liquid and gases.
a) Transverse b) Longitudinal
c) Sinusoidal d) Electromagnetic
Answer: b) Longitudinal
Explanation: Longitudinal waves involve change in volume and density of the medium. Since compressive stress can be sustained by all solid, liquid and gases, longitudinal waves can be transmitted through all.
Question 2: In the photoelectric effect, as the intensity increases, photoelectric current __________.
a) increases b) decreases
d) constant d) none of these
Answer: a) increases
Explanation: The number of photoelectrons emitted depends on the number of photons falling on the surface, which further depends on the intensity of incident light. As the intensity increases, photoelectric current increases.
Question 3: Which of the following quantities are conserved in the pair production?
a) charge and velocity b) momentum and velocity
c) charge and momentum d) charge and force
Answer: c) charge and momentum
Explanation: Conservation of charge and momentum is necessary for the pair production.
Question 4: The nature of motion of a wave packet is similar to __________.
a) waves b) quantum particle
c) photons d) classical particle
Answer: d) classical particle
Explanation: Wave packet or group of waves motion is equivalent to the motion of classical particles. These expressions are derived from the basic principle of motion.
Question 5: Which of the following functions is a wave function?
a) cot(x) b) tan(x)
b) sec(x) d) sin(x)
Answer: d) sin(x)
Explanation: Sin(x) function is continuous and single-valued. Rest all the functions are discontinuous or double-valued.
Question 6: The nature of the Schrodinger wave equation is __________.
a) parabolic b) linear
c) sinusoidal d) none of these
Answer: b) linear
Explanation: In the Schrodinger wave equation, no term has degree greater than one. Therefore nature is linear.
Question 7: When the wave function is solved using schrodinger equation, the solutions obtained are _____________
a) photon number b) atom number
c) quantum number d) schrodinger number
Answer: c) quantum number
Explanation: Quantum numbers are the solutions of Schrodinger's wave equation expressed in terms of n, I and m.
Question 8: How many values does a spin quantum number have ?
a) 1,1 b) 1,½
c) ½,½ d) +½, -½
Answer: d) +½, -½
Explanation: Spin quantum numbers have two values ½ and -½, spinning in opposite directions with the same magnitude.
Question 9: The probability of finding an electron is maximum for the quantum number _________.
a) one b) two
c) three d) four
Answer: a) one
Explanation: The probability of finding an electron is maximum in the first orbit. Since “s” orbital has a uniform probability of finding the electron in all directions, the quantum number is one.
Question 10: In d-orbital, the probability of finding an electron is along _______ direction.
a) one b) two
c) three d) four
Answer: b) two
Explanation: The probability of finding an electron in d-orbital is along two directions.