Hanzo Conard
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Hanzo Conard
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Physics Theory #3

Question 1 of 40

1

A point source is to be used with a concave mirror to produce a beam of parallel light.The source should be placed:

Select one of the following:

  • As close to the mirror as possible

  • At the center of curvature

  • Midway between the center of curvature and the focal point

  • Midway between the center of curvature and the mirror

  • Midway between the focal point and the mirror

Explanation

Question 2 of 40

1

Light from a small region of an ordinary incandescent bulb is passed through a yellow filter and then serves as the source for a Young’s double-slit experiment. Which of the following changes would cause the interference pattern to be more closely spaced?

Select one of the following:

  • Use slits that are closer together

  • Use a light source of lower intensity

  • Use a light source of higher intensity

  • Use a blue filter instead of a yellow filter

  • Move the light source further away from the slits

Explanation

Question 3 of 40

1

In an experiment to measure the wavelength of light using a double slit, it is found that the fringes are too close together to easily count them.To spread out the fringe pattern,one could:

Select one of the following:

  • Decrease the slit separation

  • Increase the slit separation

  • Increase the width of each slit

  • Decrease the width of each slit

  • None of these

Explanation

Question 4 of 40

1

If two light waves are coherent:

Select one of the following:

  • Their amplitudes are the same

  • Their frequencies are the same

  • Their wavelengths are the same

  • Their phase difference is constant

  • The difference in their frequencies is constant

Explanation

Question 5 of 40

1

The magnitude of the momentum of a particle can never exceed:

Select one of the following:

  • mc, where m is its mass

  • E/c, where E is its total energy

  • K/c, where K is its kinetic energy

  • None of the above, but there is an upper limit

  • None of the above; there is no upper limit

Explanation

Question 6 of 40

1

The units of the Planck constant h are those of:

Select one of the following:

  • Energy

  • Power

  • Momentum

  • Angular momentum

  • Frequency

Explanation

Question 7 of 40

1

The quantization of energy, E = nhf, is not important for an ordinary pendulum because:

Select one of the following:

  • The formula applies only to mass-spring oscillators

  • The allowed energy levels are too closely spaced

  • The allowed energy levels are too widely spaced

  • The formula applies only to atoms

  • The value of h for a pendulum is too large

Explanation

Question 8 of 40

1

The wavelength of light beam B is twice the wavelength of light beam B. The energy of a photon in beam A is:

Select one of the following:

  • Half the energy of a photon in beam B

  • One-fourth the energy of a photon in beam B

  • Equal to the energy of a photon in beam B

  • Twice the energy of a photon in beam B

  • Four times the energy of a photon in beam B

Explanation

Question 9 of 40

1

Which of the following electromagnetic radiations has photons with the greatest energy?

Select one of the following:

  • Blue light

  • Yellow light

  • X rays

  • Radio waves

  • Microwaves

Explanation

Question 10 of 40

1

Which of the following electromagnetic radiations has photons with the greatest momentum:

Select one of the following:

  • Blue light

  • X rays

  • Radio waves

  • Yellow light

Explanation

Question 11 of 40

1

In a photoelectric effect experiment no electrons are ejected if the frequency of the incident light is less than A/h, where h is the Planck constant and A is:

Select one of the following:

  • The maximum energy needed to eject the least energetic electron

  • The minimum energy needed to eject the least energetic electron

  • The maximum energy needed to eject the most energetic electron

  • The minimum energy needed to eject the most energetic electron

  • The intensity of the incident light

Explanation

Question 12 of 40

1

The probability that a particle is in a given small region of space is proportional to:

Select one of the following:

  • Its energy

  • Its momentum

  • The frequency of its wave function

  • The wavelength of its wave function

  • The square of the magnitude of its wave function

Explanation

Question 13 of 40

1

Maxwell’s equations are to electric and magnetic fields as equation is to the wave function for a particle:

Select one of the following:

  • Einstein’s

  • Fermi’s

  • Newton’s

  • Schr.odinger’s

  • Bohr’s

Explanation

Question 14 of 40

1

The energy of a particle in a one-dimensional trap with zero potential energy in the interior and infinite potential energy at the walls is proportional to (n = quantum number:

Select one of the following:

  • N

  • 1/n

  • 1/n^2

  • √n

Explanation

Question 15 of 40

1

A particle is trapped in a one-dimensional well with infinite potential energy at the walls Three possible pairs of energy levels are
1) n = 3 and n = 1
2) n = 3 and n = 2
3) n = 4 and n = 3
Order these pairs according to the difference in energy, least to greatest

Select one of the following:

  • 1, 2, 3

  • 3, 2, 1

  • 2, 3, 1

  • 1, 3, 2

  • 3, 1, 2

Explanation

Question 16 of 40

1

The ground state energy of an electron in a one-dimensional trap with zero potential energy in the interior and infinite potential energy at the walls:

Select one of the following:

  • Is zero

  • Decreases with temperature

  • Increases with temperature

  • Is independent of temperature

  • Oscillates with time

Explanation

Question 17 of 40

1

The ionization energy of an atom in its ground state is:

Select one of the following:

  • The energy required to remove the least energetic electron

  • The energy required to remove the most energetic electron

  • The energy difference between the most energetic electron and the least energetic electron

  • The same as the energy of a Kα-photon

  • The same as the excitation energy of the most energetic electron

Explanation

Question 18 of 40

1

In a laser:

Select one of the following:

  • Excited atoms are stimulated to emit photons by radiation external to the laser

  • The transitions for laser emission are directly to the ground state

  • The states which give rise to laser emission are usually very unstable states that decay rapidly

  • The state in which an atom is initially excited is never between two states that are involved in a stimulated emission

  • A minimum of two energy levels are required

Explanation

Question 19 of 40

1

The relation between the disintegration constant λ and the half-life T of a radioactive substance is:

Select one of the following:

  • λ = 2T

  • λ = 1/T

  • λ = 2/T

  • λT = ln2

  • λT = ln(1/2)

Explanation

Question 20 of 40

1

In a nuclear reactor the fissionable fuel is formed into pellets rather than finely ground and the pellets are mixed with the moderator This reduces the probability of

Select one of the following:

  • Non-fissioning absorption of neutrons

  • Loss of neutrons through the reactor container

  • Absorption of two neutrons by single fissionable nucleus

  • Loss of neutrons in the control rods

  • None of the above

Explanation

Question 21 of 40

1

In a subcritical nuclear reactor:

Select one of the following:

  • The number of fission events per unit time decreases with time

  • The number of fission events per unit time increases with time

  • Each fission event produces fewer neutrons than when the reactor is critical

  • Each fission event produces more neutrons than when the reactor is critical

  • None of the above

Explanation

Question 22 of 40

1

In the normal operation of a nuclear reactor:

Select one of the following:

  • Control rods are adjusted so the reactor is subcritical

  • Control rods are adjusted so the reactor is critical

  • The moderating fluid is drained

  • The moderating fluid is continually recycled

  • None of the above

Explanation

Question 23 of 40

1

Max Plank found his constant h

Select one of the following:

  • To get same result as Rayleigh and Jeans

  • To describe experimental intensity distribution of blackbody at ultraviolet region

  • To describe Compton scattering

  • To describe experimental intensity distribution of blackbody at long wavelengths

  • To describe experimental intensity distribution of blackbody at all wavelengths

Explanation

Question 24 of 40

1

Energy and momentum of photon is respectively:

Select one of the following:

  • ħω; 1/λ

  • ħω; 2πħ/λ

  • m0c^2; 2π/λ

  • m0c^2; 2πħ/λ

  • ħω; m0c^2

Explanation

Question 25 of 40

1

Nucleus of which element has no neutron:

Select one of the following:

  • Deuterium

  • Tritium

  • All nucleus for all elements

  • Hydrogen

  • Helium

Explanation

Question 26 of 40

1

The number of electron states in a shell with principal quantum number n = 3 is:

Select one of the following:

  • 3

  • 15

  • 18

  • 19

  • 25

Explanation

Question 27 of 40

1

The activity of radioactive substance is

Select one of the following:

  • –dN/dt

  • dN/dt

  • N0

  • N

  • Ndt

Explanation

Question 28 of 40

1

A hydrogen atom is in its ground state. Incident on the atom is a photon having an energy of 10.5 eV. What is the result?

Select one of the following:

  • The atom is excited to a higher allowed state

  • The atom is ionized

  • The photon passes by the atom without interaction

Explanation

Question 29 of 40

1

A hydrogen atom makes a transition from the n = 3 level to n = 2 level. It then makes a transition from the n = 2 level to the n = 1 level. Which transition results in emission of the longest-wavelength photon?

Select one of the following:

  • The first transition

  • The second transition

  • Either transition because the wavelengths are the same for both

Explanation

Question 30 of 40

1

A section of hollow pipe and a solid cylinder
have the same radius, mass, and length. They
both rotate about their long central axes with
the same angular speed. Which object has
the higher rotational kinetic energy?

Select one of the following:

  • The hollow pipe

  • The solid cylinder

  • They have the same rotational kinetic energy

  • Impossible to determine

Explanation

Question 31 of 40

1

Two spheres roll down an incline, starting
from rest. Sphere A has the same mass and
radius as sphere B, but sphere A is solid
while sphere B is hollow. Which arrives at
the bottom first?

Select one of the following:

  • Sphere A

  • Sphere B

  • Both arrive

  • At the same time

  • Impossible to determine

Explanation

Question 32 of 40

1

Two solid spheres roll down an incline,
starting from rest. Sphere A has twice the
mass and twice the radius of sphere B.
Which arrives at the bottom first?

Select one of the following:

  • Sphere A

  • Sphere B

  • Both arrive at the same time

  • Impossible to determine

Explanation

Question 33 of 40

1

Which of the following statements is not true regarding a mass- spring system that moves with simple harmonic motion in absence of friction?

Select one of the following:

  • The total energy of the system remains constant

  • The energy of the system is continually transformed between kinetic and potential energy

  • The total energy of the system is proportional to the square of the amplitude

  • The potential energy stored in the system is greatest when the mass passes through the equilibrium position.

Explanation

Question 34 of 40

1

For an object undergoing simple harmonic motion,

Select one of the following:

  • The amplitudes are usually regarded as being large

  • The acceleration is greatest when the displacement is greatest

  • The acceleration is greatest when the speed is greatest

  • The maximum potential energy is larger than the maximum kinetic energy

  • The displacement is greatest when the speed is greatest

Explanation

Question 35 of 40

1

A skater can spin faster by pulling in her arms closer to her body or spin slower by spreading her arms out from her body. This is due to

Select one of the following:

  • Conservation of momentum

  • Conservation of energy

  • Newton’s third law

  • Conservation of angular momentum

Explanation

Question 36 of 40

1

The moment of inertia of a body depends on

Select one of the following:

  • The angular velocity

  • The angular acceleration

  • The mass distribution

  • The torque acting on the body

Explanation

Question 37 of 40

1

The moment of inertia of a wheel about its axle does not depend upon its:

Select one of the following:

  • Diameter

  • Mass

  • Distribution of mass

  • Speed of rotation

Explanation

Question 38 of 40

1

A mechanical wave generally does NOT

Select one of the following:

  • Move the medium from one place to another

  • Move through a medium

  • Move through solids

  • Disturb the medium

Explanation

Question 39 of 40

1

A woman sits on a spinning stool with her arms folded. When she extends her arms, which of the following occurs

Select one of the following:

  • She increases her moment of inertia, thus increasing her angular speed

  • She increases her moment of inertia, thus decreasing her angular speed.

  • She decreases her moment of inertia, thus increasing her angular speed

  • She decreases her moment of inertia, thus decreasing her angular speed

  • Her angular speed remains constant by conservation of angular momentum

Explanation

Question 40 of 40

1

In elastic collision between the two bodies __________.

Select one of the following:

  • Only momentum of the system is conserved

  • Only the kinetic Energy of the system is conserved

  • Both the kinetic Energy and Momentum of the system remain the same

  • Total energy is not conserved

Explanation