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Relative to a stationary observer, a moving clock

Relative to a stationary observer, a moving clock

Relative to a stationary observer, a moving clock

▸ always runs slower than normal.

▸ always runs faster than normal.

▸ keeps its normal time.

▸ Any of these choices could be correct depending on the relative velocity.

Physics   mrtrombley92   44   davisdiamond   2 months ago

Radioactive particles moving at 0.80 c are measured to have a half-life of 4.3 10-8 s. What is ...

Radioactive particles moving at 0.80 c are measured to have a half-life of 4.3 10-8 s. What is ...

Radioactive particles moving at 0.80 c are measured to have a half-life of 4.3 × 10-8 s. What is their half-life when at rest?

▸ 7.2 × 10-8 s

▸ 2.6 × 10-8 s

▸ 3.4 × 10-8 s

▸ 1.6 × 10-8 s

▸ 1.7 × 10-7 s

Physics   Flaco69   28   dorkiexcici   2 months ago

Protons are sent at 0.900 c down a tube of length 27.0 m. How long does it take for the protons to ...

Protons are sent at 0.900 c down a tube of length 27.0 m. How long does it take for the protons to ...

Protons are sent at 0.900 c down a tube of length 27.0 m. How long does it take for the protons to travel this distance as measured in the lab?

▸ 100 ns

▸ 43.6 ns

▸ 229 ns

▸ 150 ns

▸ 90.0 ns

Physics   nrod1120   43   WoodyNRex   2 months ago

In the lab, charged particles are directed toward one another, each at speed 0.500 c. What is the ...

In the lab, charged particles are directed toward one another, each at speed 0.500 c. What is the ...

In the lab, charged particles are directed toward one another, each at speed 0.500 c. What is the speed of the particles moving one way with respect to the particles moving the other way?

▸ 1.25 c

▸ 1.00 c

▸ 0.800 c

▸ 0.500 c

▸ 0

Physics   mickied   30   careytran   2 months ago

In relativistic mechanics, what law or principle does not apply?

In relativistic mechanics, what law or principle does not apply?

In relativistic mechanics, what law or principle does not apply?

▸ principle of relativity

▸ conservation of momentum

▸ conservation of energy

▸ Gauss’s Law

▸ All these choices still apply under relativistic conditions.

Physics   badd99   37   bknyc123   2 months ago

In a radioactive decay, 2.37 10-3 u are converted into kinetic energy. How much kinetic energy is ...

In a radioactive decay, 2.37 10-3 u are converted into kinetic energy. How much kinetic energy is ...

In a radioactive decay, 2.37 × 10-3 u are converted into kinetic energy. How much kinetic energy is this? (1 u = 1.66 × 10-27 kg)

▸ 2.13 × 1014 J

▸ 9.31 × 108 J

▸ 3.54 × 10-13 J

▸ 3.93 × 10-30 J

▸ 1.60 × 10-13 J

Physics   gisellerol   39   whtsi_ep3   2 months ago

In a colliding-beam experiment, protons moving at 0.800 c in opposite directions strike one another. ...

In a colliding-beam experiment, protons moving at 0.800 c in opposite directions strike one another. ...

In a colliding-beam experiment, protons moving at 0.800 c in opposite directions strike one another. What is the speed of the incoming proton as viewed by the proton about to be hit?

▸ 1.60 c

▸ 0.00

▸ 0.640 c

▸ 0.976 c

▸ 0.960 c

Physics   hellchicken   67   eggr0ll   2 months ago

If two protons are heading toward one another at 0.800 c in the laboratory frame, what is the ...

If two protons are heading toward one another at 0.800 c in the laboratory frame, what is the ...

If two protons are heading toward one another at 0.800 c in the laboratory frame, what is the kinetic energy of one proton in the frame of reference of the other proton? The mass of a proton is 938 MeV/c2.

▸ 3.13 GeV

▸ 5.56 GeV

▸ 1.56 GeV

▸ 2.50 GeV

▸ 3.34 GeV

Physics   aryaelfkind   38   illusionld   2 months ago

If the velocity of a nonrelativistic object is doubled, its energy is quadrupled. This is only true ...

If the velocity of a nonrelativistic object is doubled, its energy is quadrupled. This is only true ...

If the velocity of a nonrelativistic object is doubled, its energy is quadrupled. This is only true for velocities that are very small compared with the speed of light. At what velocity would a doubling of velocity result in a doubling of energy?

▸ 0.45c

▸ 0.33c

▸ 0.11c

▸ 0.20c

▸ 0.50c

Physics   ceymorebucks24   48   mavrik8511   2 months ago

If the momentum of an electron is 1.53 MeV/c, what is its kinetic energy? The rest energy of an ...

If the momentum of an electron is 1.53 MeV/c, what is its kinetic energy? The rest energy of an ...

If the momentum of an electron is 1.53 MeV/c, what is its kinetic energy? The rest energy of an electron is 511 keV.

▸ 1.53 MeV

▸ 1.02 MeV

▸ 1.44 MeV

▸ 1.10 MeV

▸ 2.59 MeV

Physics   drew911811   41   hizzy117   2 months ago

If an object increases its speed such that its total energy is doubled, what happens to its ...

If an object increases its speed such that its total energy is doubled, what happens to its ...

If an object increases its speed such that its total energy is doubled, what happens to its relativistic momentum?

▸ The momentum is doubled.

▸ The momentum is more than doubled.

▸ The momentum is less than doubled.

▸ The momentum is quadrupled.

▸ Nothing happens to the momentum.

Physics   jesshalavi   36   tpriest1   2 months ago

If an object has its speed doubled, what happens to its relativistic momentum?

If an object has its speed doubled, what happens to its relativistic momentum?

If an object has its speed doubled, what happens to its relativistic momentum?

▸ Nothing happens.

▸ The momentum doubles.

▸ The momentum halves.

▸ The momentum more than doubles.

▸ The momentum increases a little less than double.

Physics   gslwong   42   mattloftergener   2 months ago

If a spaceship of proper length 40 m is measured to have a length 30 m, how fast is it moving?

If a spaceship of proper length 40 m is measured to have a length 30 m, how fast is it moving?

If a spaceship of proper length 40 m is measured to have a length 30 m, how fast is it moving?

▸ 0.50 c

▸ 0.81 c

▸ 0.75 c

▸ 0.66 c

▸ 0.43 c

Physics   urraberry   37   moqamoqa   2 months ago

If a proton has a kinetic energy of 1.000 GeV, what is its speed? (mp = 938 MeV/c2)

If a proton has a kinetic energy of 1.000 GeV, what is its speed? (mp = 938 MeV/c2)

If a proton has a kinetic energy of 1.000 GeV, what is its speed? (mp = 938 MeV/c2)

▸ 0.935 c

▸ 0.875 c

▸ 0.766 c

▸ 0.586 c

▸ 0.343 c

Physics   mktrujillo   23   tswinson3   2 months ago

If a proton has a kinetic energy of 1.000 GeV, what is its momentum? (mp = 938.3 MeV/c2)

If a proton has a kinetic energy of 1.000 GeV, what is its momentum? (mp = 938.3 MeV/c2)

If a proton has a kinetic energy of 1.000 GeV, what is its momentum? (mp = 938.3 MeV/c2)

▸ 1.938 GeV/c

▸ 1.000 GeV/c

▸ 938.0 GeV/c

▸ 2.872 GeV/c

▸ 1.696 GeV/c

Physics   warrenrulez   25   bcyber   2 months ago

How tall is Mount Everest from the perspective of a cosmic ray muon traveling straight down toward ...

How tall is Mount Everest from the perspective of a cosmic ray muon traveling straight down toward ...

How tall is Mount Everest from the perspective of a cosmic ray muon traveling straight down toward the Earth at 0.99c? Observers at rest relative to the ground measure the height of Mt. Everest to be 8848 m.

▸ 885 m

▸ 6.29 km

▸ 1.25 km

▸ 176 m

Physics   ericayi   26   Ranim_Saleem   2 months ago

How much mass must be converted to energy to release one million kilowatt-hours?

How much mass must be converted to energy to release one million kilowatt-hours?

How much mass must be converted to energy to release one million kilowatt-hours?

▸ 3.6 × 10-6 g

▸ 40 μg

▸ 4.0 g

▸ 3.6 × 10-12 g

▸ 40 pg

Physics   flemingpk   29   culwri204   2 months ago

How much energy is released in a nuclear reactor if the total mass of the fuel decreases by 1.0 g?

How much energy is released in a nuclear reactor if the total mass of the fuel decreases by 1.0 g?

How much energy is released in a nuclear reactor if the total mass of the fuel decreases by 1.0 g?

▸ 9.0 × 1013 J

▸ 3.0 × 1011 J

▸ 9.0 × 1014 J

▸ 3.0 × 1014 J

Physics   bioFREAK11   28   mr.pogi   2 months ago

How fast is a particle moving if its kinetic energy is equal to its rest energy?

How fast is a particle moving if its kinetic energy is equal to its rest energy?

How fast is a particle moving if its kinetic energy is equal to its rest energy?

▸ 0.00

▸ 0.57 c

▸ 0.75 c

▸ 0.87 c

▸ 0.50 c

Physics   alireads   35   omolola69   2 months ago

How does the kinetic energy of a proton change when its total energy doubles?

How does the kinetic energy of a proton change when its total energy doubles?

How does the kinetic energy of a proton change when its total energy doubles?

▸ It doubles.

▸ It more than doubles.

▸ It less than doubles.

▸ It must increase but it is not possible to say how much.

Physics   laywatdut   24   clarkh7839   2 months ago

Event 2 occurs a time t after event 1. If event 2 is caused by event 1, which of the following is true?

Event 2 occurs a time t after event 1. If event 2 is caused by event 1, which of the following is true?

[html]Event 2 occurs a time Δt after event 1. If event 2 is caused by event 1, which of the following is true?

▸ The distance between event 1 and event 2 can be anything.

▸ The distance between event 1 and event 2 is not more than c Δt.

▸ There are frames of reference in which event 2 occurs before event 1.

▸ There are frames of reference in which

Physics   xiaily   45   sherbiejr16   2 months ago

Calculate the speed of a beam of neutrons with kinetic energies of 1.0 MeV. The mass of a neutron is ...

Calculate the speed of a beam of neutrons with kinetic energies of 1.0 MeV. The mass of a neutron is ...

Calculate the speed of a beam of neutrons with kinetic energies of 1.0 MeV. The mass of a neutron is 940 MeV/c2.

▸ 799 m/s

▸ 640 km/s

▸ 9.8 × 106 m/s

▸ 1.4 × 107 m/s

Physics   biancawoods   60   someonespecial   2 months ago

At what speed would an astronaut need to travel so that he would age 4.20 years while traveling a ...

At what speed would an astronaut need to travel so that he would age 4.20 years while traveling a ...

At what speed would an astronaut need to travel so that he would age 4.20 years while traveling a distance (as measured by an Earth observer) of 4.20 ly?

▸ 1.00 c

▸ This cannot be done.

▸ 0.50 c

▸ 0.707 c

▸ 0.750 c

Physics   sarasmith06   32   Tram Nguyen   2 months ago

At what speed would a clock be moving if time dilation caused it to run slow by 50%?

At what speed would a clock be moving if time dilation caused it to run slow by 50%?

At what speed would a clock be moving if time dilation caused it to run slow by 50%?

▸ 0.500 c

▸ 0.750 c

▸ 0.250 c

▸ 0.414 c

▸ 0.866 c

Physics   mahan1994   22   heathernhull   2 months ago

At what speed is the relativistic momentum five times the value calculated classically?

At what speed is the relativistic momentum five times the value calculated classically?

At what speed is the relativistic momentum five times the value calculated classically?

▸ 0.99 c

▸ 0.98 c

▸ 0.96 c

▸ 0.80 c

▸ 0.20 c

Physics   adotey   31   dmp7474   2 months ago

An electron is accelerated from rest through a potential difference of 1.0 MV. If the rest energy of ...

An electron is accelerated from rest through a potential difference of 1.0 MV. If the rest energy of ...

An electron is accelerated from rest through a potential difference of 1.0 MV. If the rest energy of the electron is 0.511 MeV, how fast is the electron moving?

▸ 0.57 c

▸ 0.30 c

▸ 0.67 c

▸ 0.90 c

▸ 0.94 c

Physics   dex0388   46   sbbalt   2 months ago

An electron has a rest energy of 0.511 MeV. At what speed would its kinetic energy equal 1.022 MeV?

An electron has a rest energy of 0.511 MeV. At what speed would its kinetic energy equal 1.022 MeV?

An electron has a rest energy of 0.511 MeV. At what speed would its kinetic energy equal 1.022 MeV?

▸ 0.866 c

▸ 0.943 c

▸ 0.888 c

▸ 0.971 c

▸ 0.500 c

Physics   FallenOne   54   kyuhalee1   2 months ago

An astronaut in a rocket moving with a speed v = 0.6c relative to Earth performs a collision ...

An astronaut in a rocket moving with a speed v = 0.6c relative to Earth performs a collision ...

[html]An astronaut in a rocket moving with a speed v = 0.6c relative to Earth performs a collision experiment with two small steel balls and concludes the both momentum and energy are conserved. What would an Earth observer conclude?

▸ Only momentum is conserved.

▸ Only energy is conserved.

▸ Neither energy nor momentum is conserved.

▸ Both energy

Physics   drwalkinboner   73   revanchist   2 months ago

According to special relativity, what is the speed of light measured in a spaceship traveling at 0.40 c?

According to special relativity, what is the speed of light measured in a spaceship traveling at 0.40 c?

According to special relativity, what is the speed of light measured in a spaceship traveling at 0.40 c?

▸ 0.60 c

▸ 1.4 c

▸ 0.86 c

▸ 1.0 c

▸ None of these choices are correct.

Physics   djnextlevel   90   bamboofactor   2 months ago

A star like the Sun has a luminosity (energy emitted per unit time) of 3.8 1026 W. How much mass ...

A star like the Sun has a luminosity (energy emitted per unit time) of 3.8 1026 W. How much mass ...

A star like the Sun has a luminosity (energy emitted per unit time) of 3.8 × 1026 W. How much mass must be turned into energy each second to produce this power?

▸ 1.3 × 1018 kg

▸ 4.2 × 109 kg

▸ 5.6 × 105 kg

▸ 5.8 × 106 kg

▸ 1.5 × 1011 kg

Physics   abdullerz   85   crwille78   2 months ago

A spear is thrown at a very high speed. As it passes, you measure its length to be half its normal ...

A spear is thrown at a very high speed. As it passes, you measure its length to be half its normal ...

A spear is thrown at a very high speed. As it passes, you measure its length to be half its normal length. From this you conclude that the spear must be moving at

▸ 1.00 c

▸ 0.866 c

▸ 0.707 c

▸ 0.500 c

▸ Not enough information

Physics   Baradar   79   Nfernandez1991   2 months ago

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the distance from the spaceship to the star is 1.6 ly as measured from Earth, how far is the star as measured from the moving spaceship?

▸ 2.7 ly

▸ 1.9 ly

▸ 1.6 ly

▸ 1.2 ly

▸ 0.96 ly

Physics   doggerfresh   115   jennaforiero   2 months ago

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the distance from the spaceship to the star is 1.6 ly as measured from Earth, how much time passes on the spaceship while traveling to the star?

▸ 3.3 y

▸ 2.0 y

▸ 1.3 y

▸ 1.2 y

▸ 0.96 y

Physics   Jimmyhighroller   79   clubber25   2 months ago

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the ...

A spaceship is observed from the Earth to be moving toward a star at a speed of 0.80 c. If the distance from the spaceship to the star is 1.6 ly as measured from Earth, how long does an observer on Earth find that it takes for the spaceship to reach the star?

▸ 2.0 y

▸ 2.1 y

▸ 1.6 y

▸ 1.2 y

▸ 0.96 y

Physics   misserz0210   85   Ludacris2065   2 months ago

A spaceship is observed by a stationary observer to be moving at 0.600 c. A laser beam is directed ...

A spaceship is observed by a stationary observer to be moving at 0.600 c. A laser beam is directed ...

A spaceship is observed by a stationary observer to be moving at 0.600 c. A laser beam is directed straight ahead from the front of the spaceship. How fast does the laser beam travel relative to the stationary observer?

▸ 4.00 c

▸ 1.60 c

▸ 1.00 c

▸ 0.750 c

▸ 0.480 c

Physics   anthonyaooo   48   chemcal   2 months ago

A spaceship is 25 m wide and 100 m long. When traveling at 0.80 c (in a direction parallel to its ...

A spaceship is 25 m wide and 100 m long. When traveling at 0.80 c (in a direction parallel to its ...

A spaceship is 25 m wide and 100 m long. When traveling at 0.80 c (in a direction parallel to its length), what is its observed width?

▸ 42 m

▸ 25 m

▸ 16 m

▸ 15 m

▸ 20 m

Physics   katiemarie   28   whtsi_ep3   2 months ago

A rocket speeding by the Earth is roughly cylindrical in shape and oriented such that its axis is ...

A rocket speeding by the Earth is roughly cylindrical in shape and oriented such that its axis is ...

[html]A rocket speeding by the Earth is roughly cylindrical in shape and oriented such that its axis is parallel to its velocity. At rest, it is measured to have a radius of 15 m and a length of 150 m. When speeding by, its volume is measured to be 4.24 × 104 m3. What is its speed?

▸ 0.917 c

▸ 0.774 c

▸ 0.678 c

▸ Insufficient

Physics   Neurosciencie   27   parrothead   2 months ago

A rocket speeding by the Earth at 0.917c is roughly cylindrical in shape and oriented such that its ...

A rocket speeding by the Earth at 0.917c is roughly cylindrical in shape and oriented such that its ...

[html]A rocket speeding by the Earth at 0.917c is roughly cylindrical in shape and oriented such that its axis is parallel to its velocity. At rest, it is measured to have a radius of 15 m and a length of 150 m. When speeding by, what is its volume as measured by observers on Earth?

▸ 6.78 × 103 m3

▸ 1.70 × 104 m3

▸

Physics   Jchanis15   38   dioxy186   2 months ago

A pion has a mean lifetime of 25 ns in its own rest frame. A beam of pions traveling through the ...

A pion has a mean lifetime of 25 ns in its own rest frame. A beam of pions traveling through the ...

A pion has a mean lifetime of 25 ns in its own rest frame. A beam of pions traveling through the laboratory at a speed of 0.60 c is measured to have a mean lifetime of

▸ 21 µs.

▸ 20 ns.

▸ 31 ns.

▸ 31 µs.

Physics   trixr4kids   26   Chintan13   2 months ago

A passenger is on a spaceship traveling at 0.8 c. The passenger observes that her watch

A passenger is on a spaceship traveling at 0.8 c. The passenger observes that her watch

A passenger is on a spaceship traveling at 0.8 c. The passenger observes that her watch

▸ is running slow.

▸ is running fast.

▸ is keeping time as usual.

▸ is running slow if the ship is traveling in the positive direction.

▸ is running slow if the ship is traveling in the negative direction.

Physics   npdtan92   24   letssdoothiss   2 months ago