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1.8 Relativistic Mechanics

Irodov Problems 1.340 to 1.388.

  • 49problems
  • 110figures
  • Difficulty2.7avgDifficulty: 2 rated 1, 20 rated 2, 20 rated 3, 7 rated 4, 0 rated 5; mean 2.7.
  • Uniqueness3.1avgUniqueness: 2 rated 1, 9 rated 2, 20 rated 3, 17 rated 4, 1 rated 5; mean 3.1.
No.TitleDifficultyUniquenessMethods
1.340Small Contraction, Not Small SpeedDifficulty 1 of 5Uniqueness 1 of 5length contraction · approximation expansion · limiting cases
1.341Each Side Shrinks by Its AngleDifficulty 3 of 5Uniqueness 3 of 5length contraction · vector decomposition · limiting cases
1.342Only One Leg of the Rod ShrinksDifficulty 2 of 5Uniqueness 3 of 5length contraction · vector decomposition · lorentz transformation
1.343Only the Height Is ContractedDifficulty 3 of 5Uniqueness 3 of 5length contraction · vector decomposition · limiting cases
1.344How Fast to Lose Two PercentDifficulty 1 of 5Uniqueness 1 of 5time dilation · frames of reference · limiting cases
1.345Two Timings Fix One Proper LengthDifficulty 2 of 5Uniqueness 3 of 5length contraction · time dilation · frames of reference
1.346The Lifetime Ratio Is GammaDifficulty 2 of 5Uniqueness 2 of 5time dilation · invariant interval · frames of reference
1.347The Muon Sees a Shorter DistanceDifficulty 2 of 5Uniqueness 3 of 5time dilation · length contraction · frames of reference
1.348One Clock Times a Contracted GapDifficulty 2 of 5Uniqueness 2 of 5length contraction · time dilation · frames of reference
1.349Two Simultaneities, Two Lengths, One RodDifficulty 3 of 5Uniqueness 4 of 5length contraction · lorentz transformation · frames of reference
1.350Two Rods, One Clock, One GapDifficulty 4 of 5Uniqueness 4 of 5length contraction · relative motion · frames of reference
1.351Simultaneous for Them, Not for UsDifficulty 3 of 5Uniqueness 3 of 5lorentz transformation · length contraction · frames of reference
1.352Two Marks Made at Two Different TimesDifficulty 3 of 5Uniqueness 4 of 5length contraction · frames of reference · lorentz transformation
1.353Each Rod Sees the Other LagDifficulty 3 of 5Uniqueness 4 of 5time dilation · length contraction · lorentz transformation · frames of reference
1.354Same Moment, Two Different AnswersDifficulty 3 of 5Uniqueness 4 of 5lorentz transformation · frames of reference · length contraction
1.355The Point Where Both Clocks AgreeDifficulty 3 of 5Uniqueness 4 of 5lorentz transformation · frames of reference · limiting cases
1.356No Boost Outruns a CauseDifficulty 3 of 5Uniqueness 4 of 5lorentz transformation · frames of reference · invariant interval
1.357The Interval Answers Both QuestionsDifficulty 3 of 5Uniqueness 4 of 5invariant interval · lorentz transformation · frames of reference
1.358The Transverse Component Changes TooDifficulty 2 of 5Uniqueness 2 of 5lorentz transformation · frames of reference · vector decomposition
1.359The Gap Closes Faster Than Anything MovesDifficulty 2 of 5Uniqueness 4 of 5relative motion · frames of reference · lorentz transformation
1.360Compose the Speeds, Then ContractDifficulty 3 of 5Uniqueness 3 of 5length contraction · lorentz transformation · relative motion
1.361Pythagoras Loses a Relativistic TermDifficulty 2 of 5Uniqueness 3 of 5lorentz transformation · relative motion · vector decomposition
1.362Two Gammas Multiply Across the BoostDifficulty 3 of 5Uniqueness 3 of 5lorentz transformation · time dilation · frames of reference
1.363The Angle a Boost BendsDifficulty 2 of 5Uniqueness 2 of 5lorentz transformation · frames of reference · vector decomposition · relative motion
1.364A Rod Tilted by Disagreeing ClocksDifficulty 4 of 5Uniqueness 4 of 5lorentz transformation · length contraction · frames of reference
1.365The Clock Transforms TooDifficulty 4 of 5Uniqueness 3 of 5lorentz transformation · frames of reference · calculus of motion
1.366A Year at Ten GravitiesDifficulty 4 of 5Uniqueness 3 of 5relativistic dynamics · differential equation · frames of reference · approximation expansion
1.367The Crew Ages Only LogarithmicallyDifficulty 3 of 5Uniqueness 4 of 5time dilation · relativistic dynamics · calculus of motion
1.368Inertia from the Square Root's EdgeDifficulty 2 of 5Uniqueness 2 of 5relativistic dynamics · approximation expansion
1.369Rest Mass over a Shrinking BoxDifficulty 2 of 5Uniqueness 3 of 5length contraction · relativistic dynamics
1.370Half a Percent Short of LightDifficulty 2 of 5Uniqueness 2 of 5relativistic dynamics · invariant interval · approximation expansion
1.371The Excess Factor Is Just GammaDifficulty 2 of 5Uniqueness 2 of 5relativistic dynamics · limiting cases
1.372The Same Two Tenths of c Cost Three Times MoreDifficulty 2 of 5Uniqueness 3 of 5work energy · relativistic dynamics · approximation expansion
1.373Where Motion Doubles a Particle's EnergyDifficulty 2 of 5Uniqueness 2 of 5relativistic dynamics · limiting cases
1.374How Slow Is Slow EnoughDifficulty 3 of 5Uniqueness 4 of 5relativistic dynamics · approximation expansion · limiting cases
1.375Momentum from Kinetic Energy AloneDifficulty 2 of 5Uniqueness 3 of 5relativistic dynamics · invariant interval · limiting cases
1.376Momentum and Energy per Unit TimeDifficulty 2 of 5Uniqueness 2 of 5momentum flux · relativistic dynamics · limiting cases
1.377Both Frames Agree on the PressureDifficulty 4 of 5Uniqueness 4 of 5momentum flux · length contraction · frames of reference · relativistic dynamics
1.378Momentum Grows Forever, Speed SaturatesDifficulty 2 of 5Uniqueness 3 of 5relativistic dynamics · impulse · calculus of motion · limiting cases
1.379Hyperbolic Motion Hides a Constant ForceDifficulty 3 of 5Uniqueness 3 of 5relativistic dynamics · calculus of motion · limiting cases
1.380Two Inertias, One Rest MassDifficulty 3 of 5Uniqueness 4 of 5relativistic dynamics · vector decomposition · limiting cases
1.381Energy and Momentum Are One VectorDifficulty 3 of 5Uniqueness 4 of 5lorentz transformation · four vectors · relativistic dynamics · invariant interval
1.382Chasing a Photon Lowers Its EnergyDifficulty 2 of 5Uniqueness 3 of 5lorentz transformation · relativistic doppler · four vectors
1.383Every Frame Agrees on Rest MassDifficulty 2 of 5Uniqueness 3 of 5relativistic dynamics · invariant interval · four vectors
1.384The Frame Where Momentum VanishesDifficulty 3 of 5Uniqueness 3 of 5relativistic dynamics · invariant interval · frames of reference · collisions
1.385Sticking Together Creates New Rest MassDifficulty 3 of 5Uniqueness 3 of 5relativistic dynamics · four vectors · collisions · momentum conservation
1.386The Price of a Stationary TargetDifficulty 3 of 5Uniqueness 4 of 5relativistic dynamics · invariant interval · frames of reference · collisions
1.387When the Other Two Move TogetherDifficulty 4 of 5Uniqueness 4 of 5relativistic dynamics · invariant interval · optimization · momentum conservation
1.388The Rocket Adds Rapidity Not SpeedDifficulty 4 of 5Uniqueness 5 of 5variable mass · relativistic dynamics · lorentz transformation · differential equation