Physics - 26, 27, 28

A boat can travel 4.0 m/s in still water. With what speed, relative to the shore, does it move in a river that is flowing at 1.0 m/s if the boat is heading upstream? A) 3.0 m/s B) 4.1 m/s C) 4.8 m/s D) 5.0 m/s

A

A hydrogen atom is in the 6h state. How many electrons are allowed in this state? A) 22 B) 18 C) 14 D) 10

A

A hydrogen atom is in the 6h state. Which of the following could be an orbital quantum number? A) 5 B) 6 C) 7 D) 8

A

A monochromatic light is incident on the surface of a metal with work function 2.50 eV. If a 1.0-V stopping potential is required to make the photocurrent zero, what is the wavelength of light? A) 354 nm B) 423 nm C) 497 nm D) 744 nm

A

A neutral atom has an electron configuration of 1s^2 2s^2 2p^6. If a neutral atom holds one additional electron, what is the ground state configuration? A) 1s^2 2s^2 2p^6 3s^1 B) 1s^2 2s^2 2p^7 C) 1s^2 2s^3 2p^6 D) none of the given answers

A

An electron inside a hydrogen atom is confined to within a space of about 0.110 nm. If the electron mass is 9.11 x 10^-31 kg, what is the uncertainty in the electron's velocity? A) 1.05 x 10^6 m/s B) 1.50 x 10^6 m/s C) 1.05 x 10^8 m/s D) 1.50 x 10^8 m/s

A

An electron is accelerated by a potential difference of 100 V. What is its wavelength? A) 0.122 nm B) 0.212 nm C) 0.221 nm D) 0.313 nm

A

An electron is accelerated through 100 kV. By what factor has its mass increased with respect to its rest mass? A) 1.20 B) 1.55 C) 4.25 D) 8.00

A

An electron is accelerated through a potential difference of 150 V. What is its wavelength? A) 0.1 nm B) 1 nm C) 1 mm D) 1 cm

A

During a reaction, an element loses 4.8 x 10-28 kg of mass. How much energy (in Joules) is released? A) 4.3 x 10^-11 J B) 1.4 x 10^-19 J C) 1.6 x 10^-36 J D) 5.3 x 10^-45 J

A

How much energy would be released if 2.0 kg of material was lost during a reaction? A) 1.8 x 10^17 J B) 1.5 x 10^16 J C) 6.0 x 10^8 J D) 4.7 x 10^-8 J

A

If r1 is the smallest orbital radius around a single proton, then r6 is equal to A) 36r1. B) 12r1. C) 6r1. D) 2.45r1.

A

If the velocity of your spaceship goes from 0.3 c to 0.6 c, then your mass will increase by A) 19%. B) 38%. C) 100%. D) 200%.

A

In making a transition from state n = 1 to state n = 2, the hydrogen atom must A) absorb a photon of energy 10.2 eV. B) emit a photon of energy 10.2 eV. C) absorb a photon of energy 13.58 eV. D) emit a photon of energy 13.58 eV.

A

The amount of energy equivalent to two kilogram of mass at rest is A) 18 x 10^16 J. B) 3.0 x 10^8 J. C) 9.0 x 10^16 J. D) none of the given answers

A

The atomic bomb that was dropped on Nagasaki in 1945 killed 140,000 people, helping to end World War II on the next day. It released energy equivalent to that of 20,000 tons of TNT explosive. How much mass was converted to energy when this took place? (1000 tons of TNT = 4.3 x 10^12 J) Incidentally, modern H-bombs have energy yields 1000 times as much! A) 1 g B) 10 g C) 100 g D) 1 kg

A

The closest star to our solar system is Alpha Centauri, which is 4.30 light years away. A spaceship with a constant speed of 0.800c relative to the Earth travels toward the star. How much time would elapse on a clock on board the spaceship? A) 3.23 y B) 4.40 y C) 5.15 y D) 5.38 y

A

The closest star to our solar system is Alpha Centauri, which is 4.30 light years away. A spaceship with a constant speed of 0.800c relative to the Earth travels toward the star. What distance does the space ship travel according to a passenger on the ship? A) 2.58 ly B) 3.52 ly C) 4.12 ly D) 4.30 ly

A

The energy of an electron state has an uncertainty of about 0.500 eV. What is the uncertainty in the life-time of the level? A) 1.32 x 10-15 s B) 8.28 x 10-15 s C) 1.32 x 10-11 s D) 8.28 x 10-11 s

A

What is the de Broglie wavelength of a ball of mass 200 g moving with a speed of 30 m/s? A) 1.1 x 10^-34 m B) 2.2 x 10^-34 m C) 4.5 x 10^-28 m D) 6.7 x 10^-27 m

A

What is the ionization energy of singly ionized helium? A) 54.4 eV B) 27.2 eV C) 13.6 eV D) none of the given answers

A

What is the shortest-wavelength X-ray photon emitted in an X-ray tube subject to 50 kV? A) 0.025 nm B) 0.25 nm C) 2.5 nm D) none of the given answers

A

What is the total energy of an electron moving with a speed of 0.95c? A) 2.6 x 10^-13 J B) 8.2 x 10^-14 J C) 1.1 x 10^-13 J D) 1.2 x 10^-14 J

A

What is the wavelength of the matter wave associated with an electron moving with a speed of 2.5 x 10^7 m/s? A) 29 pm B) 35 pm C) 47 pm D) 53 pm

A

When light of wavelength 350 nm is incident on a metal surface, the stopping potential of the photoelectrons is 0.500 eV. What is the maximum kinetic energy of the electron? A) 0.500 eV B) 3.04 eV C) 3.54 eV D) 4.12 eV

A

A baseball has mass 143 g and speed 45.0 m/s, with the speed known to within 0.100%. What is the minimum uncertainty in the position of the baseball? A) 1.56 x 10^-32 m B) 1.65 x 10^-32 m C) 1.56 x 10^-30 m D) 1.65 x 10^-30 m

B

A boat can travel 4.0 m/s in still water. With what speed, relative to the shore, does it move in a river that is flowing at 1.0 m/s if the boat is heading straight across the river? A) 3.0 m/s B) 4.1 m/s C) 4.8 m/s D) 5.0 m/s

B

A hydrogen atom in the ground state absorbs a photon of energy 12.09 eV. To which state will the electron make a transition? A) n = 2 B) n = 3 C) n = 4 D) n = 5

B

A measurement of an electron's speed is 2.0 x 10^6 m/s and has an uncertainty of 10%. What is the minimum uncertainty in position? A) 0.29 nm B) 0.58 nm C) 0.87 nm D) 1.2 nm

B

A person of mass 50 kg has a wavelength of 4.4 x 10^-36 m when running. How fast is she running? A) 2.0 m/s B) 3.0 m/s C) 4.0 m/s D) 5.0 m/s

B

A spaceship moves away from the Earth with a speed of 0.80c. The spaceship then fires a missile with a speed of 0.50c relative to the spaceship. What is the velocity of the missile measured by observers on the Earth if the missile is fired toward the Earth? A) 0.30c B) 0.50c C) 0.93c D) 1.3c

B

An electron is accelerated by a potential difference of 100 V. What is its kinetic energy? A) 1.26 x 10^-17 J B) 1.62 x 10^-17 J C) 2.16 x 10^-17 J D) 2.61 x 10^-17 J

B

At what rate are photons emitted by a 50-W sodium vapor lamp? (Assume that the lamp's light is monochromatic and of wavelength 589 nm.) A) 1.0 x 10^20/s B) 1.5 x 10^20/s C) 2.0 x 10^20/s D) 2.5 x 10^20/s

B

Consider ground-state helium holding two electrons in orbit. If one of the electrons has quantum numbers (n, l, ml, ms) of 1, 0, 0, -1/2 respectively, the quantum numbers for the other electron will be A) 1, 1, 0, -1/2. B) 1, 0, 0, +1/2. C) 1, 1, 1, +1/2. D) none of the given answers

B

How many joules of energy are required to accelerate one kilogram of mass from rest to a velocity of 0.866 c? A) 1.8 x 10^17 J B) 9.0 x 10^16 J C) 3.0 x 10^3 J D) none of the given answers

B

How much energy, in joules, is carried by a photon of wavelength 660 nm? A) 1.46 x 10-48 J B) 3.01 x 10-19 J C) 6.63 x 10-34 J D) none of the given answers

B

If the scattering angle in Compton's scattering is 90°. What is the wavelength shift? A) 1.22 x 10-12 m B) 2.43 x 10-12 m C) 3.65 x 10-12 m D) 4.85 x 10-12 m

B

In a hydrogen atom, a given electron has n = 7. How many values can l have? A) 6 B) 7 C) 15 D) 98

B

In a nuclear plant, 10^17 J of energy is available from mass conversion. How much mass was lost? A) 0.1 kg B) 1 kg C) 10 kg D) 100 kg

B

Suppose that the speed of an electron traveling 2000 m/s is known to an accuracy of 1 part in 105 (i.e., within 0.001%). What is the greatest possible accuracy within which we can determine the position of this electron? A) 2.9 mm B) 5.8 mm C) 8.7 mm D) 1.2 cm

B

The electron of a hydrogen atom makes a transition from the n = 5 state to the n = 2 state. What is the wavelength of the emitted photon? A) 344 nm B) 434 nm C) 443 nm D) 523 nm

B

The length of a spaceship is 10 m when it is at rest. If the spaceship travels by you with a speed of 0.70c, what length does it appear to you? A) 5.5 m B) 7.1 m C) 12 m D) 18 m

B

The values of n and l for a 4f sub shell are A) n = 4, l = 4. B) n = 4, l = 3. C) n = 3, l = 3. D) n = 4, l = 2.

B

What is the frequency of the most intense radiation from an object with temperature 100°C? A) 2.9 x 10^-5 Hz B) 3.9 x 10^13 Hz C) 1.0 x 10^13 Hz D) 1.0 x 10^11 Hz

B

What is the ionization energy of the neutral hydrogen atom? A) 27.2 eV B) 13.6 eV C) 6.8 eV D) none of the given answers

B

What is the wavelength of the matter wave associated with a ball of mass 0.50 kg moving with a speed of 25 m/s? A) 3.5 x 10^-35 m B) 5.3 x 10^-35 m C) 3.5 x 10^-33 m D) 5.3 x 10^-33 m

B

When light of wavelength 350 nm is incident on a metal surface, the stopping potential of the photoelectrons is 0.500 eV. What is the work function of the metal? A) 0.500 eV B) 3.04 eV C) 3.54 eV D) 4.12 eV

B

X-rays with a wavelength of 0.00100 nm are scattered by free electrons at 130°. What is the kinetic energy of each recoil electron? A) 2.5 MeV B) 5.0 MeV C) 7.5 MeV D) 10 MeV

B

A fast spaceship is traveling with a speed of 0.80c. How fast would light travel from the headlights of the ship relative to a stationary observer? A) 0.20c B) 0.80c C) 1.0c D) 1.8c

C

A hydrogen atom is in the 6h state. Determine the principal quantum number. A) 0 B) 5 C) 6 D) 7

C

A metal has a work function of 4.5 e. Find the maximum kinetic energy of the photoelectrons if the wavelength of light is 250 nm. A) zero B) 0.37 eV C) 0.46 eV D) 0.53 eV

C

A meter stick is moving toward you with a speed of 0.80c. What is its length? A) zero B) 0.40 m C) 0.60 m D) 1.0 m

C

A neutral atom has an electron configuration of 1s^2 2s^2 2p^6 3s^2 3p^2. What is its atomic number? A) 5 B) 11 C) 14 D) 20

C

A neutral atom has electron configuration 1s^2 2s^2 2p^6 3s^2 3p^2. What element is this? A) carbon B) nitrogen C) silicon D) germanium

C

A set of twins, Andrea and Courtney, are initially 10 years old. While Courtney remains on Earth, Andrea rides on a space ship which travels away from Earth at a speed of 0.6c for five years (as measured by Courtney), then turns around and comes back at 0.6c. When Andrea returns, Courtney is 20 years old. How old is Andrea upon her return? A) 10 years B) 12 years C) 18 years D) 20 years

C

A spaceship moves away from the Earth with a speed of 0.80c. The spaceship then fires a missile with a speed of 0.50c relative to the spaceship. What is the velocity of the missile measured by observers on the Earth if the missile is fired away from the Earth? A) 0.30c B) 0.50c C) 0.93c D) 1.3c

C

An electron is known to be confined to a region of width 0.1 nm. What is an approximate expression for the least kinetic energy it could have, in eV? A) 2.7 eV B) 3.2 eV C) 3.8 eV D) 4.3 eV

C

An electron is moving about a single proton in an orbit characterized by n = 4. How many of the electron's de Broglie wavelengths fit into the circumference of this orbit? A) 1 B) 2 C) 4 D) 16

C

An electron is traveling at 0.85c. What is its mass? (The rest mass is 9.11 x 10^-31 kg.) A) 1.4 x 10^-29 kg B) 7.2 x 10^-30 kg C) 1.7 x 10^-30 kg D) 2.4 x 10^-30 kg

C

High-energy photons are used to bombard an unknown metal. The strongest peak is found for X-rays with an energy of 66 keV. What is the atomic number of the metal? A) 80 B) 81 C) 82 D) 83

C

How much energy is carried by a photon with frequency 110 GHz? A) 1.1 x 10^-20 J B) 1.4 x 10^-22 J C) 7.3 x 10^-23 J D) 1.3 x 10^-25 J

C

In a hydrogen atom, a given electron has l = 7. How many values can ml have? A) 6 B) 7 C) 15 D) 98

C

In a ruby laser, an electron jumps from a higher energy level to a lower one. If the energy difference between the two levels is 1.8 eV, what is the wavelength of the emitted photon? A) 469 nm B) 649 nm C) 694 nm D) 964 nm

C

In state n = 1, the energy of the hydrogen atom is -13.58 e. What is its energy in state n = 2? A) -6.79 eV B) -4.53 eV C) -3.40 eV D) -1.51 eV

C

One 20-year-old twin brother takes a space trip with a speed of 0.80c for 30 years according to a clock on the spaceship. Upon returning to the Earth, what is his own age and the age of the Earth-based twin brother? A) 20;30 B) 30;50 C) 50;70 D) 70;90

C

The kinetic energy of a proton is 80% of its total energy. What is the speed of the proton? A) 0.02c B) 0.87c C) 0.98c D) 1.0c

C

The radius of a typical nucleus is about 5.0 ̨ 10-15 m. Assuming this to be the uncertainty in the position of a proton in the nucleus, estimate the uncertainty in the proton's energy (in eV). A) 0.4 MeV B) 0.6 MeV C) 0.8 MeV D) 1.0 MeV

C

The wavelength of a ruby laser is 694.3 nm. What is the energy difference between the two energy states involved in laser action? A) 1.537 eV B) 1.646 eV C) 1.786 eV D) 1.812 eV

C

What frequency of electromagnetic radiation has energy 4.7 x 10-25 J? A) 710 kHz B) 4.7 MHz C) 710 MHz D) 1.4 GHz

C

What is the electron configuration for Li which has three electrons? A) 1s^3 B) 1s^1 2s^2 C) 1s^2 2s^1 D) 1s^2 1p^1

C

What is the photon energy of red light having wavelength 640 nm? A) 1.13 x 10-19 J B) 1.31 x 10-19 J C) 3.11 x 10-19 J D) 1.94 x 10-19 J

C

What is the wavelength corresponding to the most intense light emitted by a giant star of surface temperature 5000 K? A) 576 nm B) 578 nm C) 580 nm D) 582 nm

C

You are in a rocket traveling away from the Sun at 0.95c. You measure the speed of light from the Sun to be A) 0.05c. B) 0.95c. C) 1.0c. D) cannot be determined without knowing the frequency of the light

C

A boat can travel 4.0 m/s in still water. With what speed, relative to the shore, does it move in a river that is flowing at 1.0 m/s if the boat is heading downstream? A) 3.0 m/s B) 4.1 m/s C) 4.8 m/s D) 5.0 m/s

D

A hydrogen atom is in the 6h state. Which one of the following is not a magnetic quantum number? A) 0 B) 2 C) 4 D) 6

D

A spaceship takes a nonstop journey to a planet and returns in 10 hours according to a clock on the spaceship. If the speed of the spaceship is 0.80c, how much time has elapsed on the Earth? A) 3.2 h B) 7.0 h C) 15 h D) 17 h

D

An electron has a wavelength of 0.123 nm. What is its energy in e? (This energy is not in the relativistic region.) A) 20 eV B) 60 eV C) 80 eV D) 100 eV

D

An electron is accelerated by a potential difference of 100 V. What is its momentum in kgm/s? A) 3.45 x 10^-24 B) 3.54 x 10^-24 C) 4.53 x 10^-24 D) 5.43 x 10^-24

D

During a reaction, 1.7 x 10^-4 J of energy is released. What change of mass would cause this? A) 5.1 x 10^-4 kg B) 1.5 x 10^-13 kg C) 4.8 x 10^-18 kg D) 1.9 x 10^-21 kg

D

How fast should a moving clock travel if it is to be observed by a stationary observer as running at one-half its normal rate? A) 0.50c B) 0.65c C) 0.78c D) 0.87c

D

How fast would a rocket ship have to move to contract to half of its proper length (as observed by a stationary object)? A) 0.50c B) 0.65c C) 0.78c D) 0.87c

D

How many electrons will fit into a 4f sub shell? A) 3 B) 4 C) 7 D) 14

D

How much energy is carried by a photon with a frequency of 100,000 GHz? A) 4.73 x 10^-42 J B) 4.37 x 10^-24 J C) 6.63 x 10^-24 J D) 6.63 x 10^-20 J

D

How much mass is lost during a reaction in which 1.7 ̨ 108 MeV of energy is released? A) 1.8 x 10^-8 kg B) 5.7 x 10^-9 kg C) 1.9 x 10^-17 kg D) 3.0 x 10^-22 kg

D

In a hydrogen atom, an electron with n = 7 can exist in how many different quantum states? A) 6 B) 7 C) 15 D) 98

D

The binding energy of the hydrogen atom in its ground state is -13.6 eV. What is the energy when it is in the n = 5 state? A) 2.72 eV B) -2.72 eV C) 0.544 eV D) -0.544 eV

D

The closest star to our solar system is Alpha Centauri, which is 4.30 light years away. A spaceship with a constant speed of 0.800c relative to the Earth travels toward the star. How much time would elapse on a clock on the Earth? A) 3.23 y B) 4.40 y C) 5.15 y D) 5.38 y

D

The kinetic energy of a proton is 80% of its total energy. What is the momentum in kgm/s of the proton? A) 5.0 x 10^-19 kgm/s B) 2.5 x 10^-19 kgm/s C) 5.0 x 10^-18 kgm/s D) 2.5 x 10^-18 kgm/s

D

Two spaceships are traveling through space at 0.60 c relative to the Earth. If the ships are headed directly toward each other, what is their approach velocity, as measured by a person on either craft? A) 1.2c B) c C) 0.60c D) none of the given answers

D

What energy is released (in MeV) during a reaction in which 1.67 x 10^-25 kg of material is converted to energy? A) 5.0 x 10^-14 MeV B) 4.1 x 10^-7 MeV C) 3.1 x 10^-4 MeV D) 9.4 x 10^4 MeV

D

What frequency of electromagnetic radiation has an energy of 58.1 mu eV? A) 1.4 MHz B) 711 MHz C) 7.1 GHz D) 14 GHz

D

What is the momentum in kgm/s of a proton when it is moving with a speed of 0.60c? A) 1.2 x 10-19 kgm/s B) 1.5 x 10-19 kgm/s C) 3.0 x 10-19 kgm/s D) 3.8 x 10-19 kgm/s

D

What is the speed of a proton if its mass is twice its rest mass? A) 0.50c B) 0.68c C) 0.73c D) 0.87c

D

When light of wavelength 350 nm is incident on a metal surface, the stopping potential of the photoelectrons is 0.500 eV. What is the threshold frequency? A) 3.47 x 10^14 Hz B) 3.74 x 10^14 Hz C) 4.73 x 10^14 Hz D) 7.34 x 10^14 Hz

D

X-rays of wavelength 0.20 nm are scattered by a metal. The wavelength shift is observed to be 2.0 x 10^-12 m at a certain scattering angle measured relative to the incoming X-ray. What is the scattering angle? A) 20° B) 40° C) 60° D) 80°

D