Problems

Title	Difficulty	Solved	Accept.
75. Effective Anchor+20Med.	Med.	1	50.0%
1. Biaxial Plate PendulumHard	Hard	9	47.4%
2. Springy Hoop PendulumMed.	Med.	9	29.0%
3. Squirt Gun EnergyMed.	Med.	9	75.0%
4. Work in a Moving FrameEasy	Easy	30	37.5%
5. Trailing SledHard	Hard	6	37.5%
6. Piezometer Elevation DropMed.	Med.	5	62.5%
7. Sag and LiftMed.	Med.	2	20.0%
8. Spring Lift-OffMed.	Med.	7	77.8%
9. Centrifugal BuoyancyMed.	Med.	5	83.3%
10. Sweeping Satellite in Dust CloudMed.	Med.	3	75.0%
11. Ambiguous InelasticityEasy	Easy	12	63.2%
12. Rolling on a Moving RampMed.	Med.	5	83.3%
13. Energy of a Robotic ArmMed.	Med.	5	71.4%
14. Center of Mass ShiftMed.	Med.	2	50.0%
15. Reinforced TripodMed.	Med.	1	—
16. Rolling Cylinder on a SpringMed.	Med.	6	75.0%
17. Center of Percussion of a DumbbellMed.	Med.	3	60.0%
18. Elevator OscillatorsMed.	Med.	5	83.3%
19. Double Conical PendulumMed.	Med.	3	60.0%
20. Rolling to Slipping TransitionMed.	Med.	2	66.7%
21. Oscillator in a Shrinking CavityMed.	Med.	3	100.0%
22. Force on a Shifting AxisMed.	Med.	3	100.0%
23. Adiabatic Mass LossMed.	Med.	5	100.0%
24. Compound-Wheel CascadeMed.	Med.	0	—
25. The Hexagonal Space Station IMed.	Med.	8	29.3%
26. The Hexagonal Space Station IIHard	Hard	6	50.0%
27. The Hexagonal Space Station IIIHard	Hard	2	100.0%
28. Coincident FrequenciesMed.	Med.	3	37.5%
29. 3D Ring FrictionMed.	Med.	4	66.7%
30. Sequential Frictional StoppingMed.	Med.	4	57.1%
31. Coupled Friction on SledEasy	Easy	9	60.0%
32. Momentum Flux TensionMed.	Med.	3	75.0%
33. Dust Drag on HemispheresMed.	Med.	2	100.0%
34. Hidden Mass Spring PendulumMed.	Med.	2	40.0%
35. Density Error PropagationEasy	Easy	6	66.7%
36. Sandwiched Slipping BlocksMed.	Med.	3	42.9%
37. The PH-SL0 Droid IMed.	Med.	4	40.0%
38. The PH-SL0 Droid IIHard	Hard	2	40.0%
39. The PH-SL0 Droid IIIHard	Hard	2	100.0%
40. Restricted Collision StatesMed.	Med.	5	83.3%
41. Turntable String TensionMed.	Med.	5	62.5%
42. Randomly Sampled OrbitMed.	Med.	3	60.0%
43. Free Rod CollisionMed.	Med.	4	33.3%
44. Heavy Hoop PendulumMed.	Med.	6	66.7%
45. Frame-Dependent Launch EnergyEasy	Easy	7	87.5%
46. Slipping Stack AccelerationMed.	Med.	4	80.0%
47. Friction Over a Curved PathMed.	Med.	5	100.0%
48. Impulsive FrictionMed.	Med.	5	100.0%
49. Tapered Capillary TubeMed.	Med.	8	100.0%
50. Turntable Doppler SpectrumMed.	Med.	5	62.5%
51. Near-Side Tidal WeightMed.	Med.	2	33.3%
52. Bouncing Particle and Massive BlockHard	Hard	4	66.7%
53. Constant Power ScalingEasy	Easy	7	46.7%
54. Cradled DescentHard	Hard	1	—
55. The Hidden HorizontalEasy	Easy	1	25.0%
56. Twin CavitiesMed.	Med.	0	—
57. Pegged PendulumMed.	Med.	0	—
58. Critical Speed LimitMed.	Med.	1	33.3%
59. Cascading Slip ThresholdsHard	Hard	1	—
60. Threshold to TumbleMed.	Med.	0	—
61. Compounded Spring StiffnessMed.	Med.	0	—
62. Quarter-Period RendezvousEasy	Easy	1	—
63. Pumping the PendulumMed.	Med.	0	—
64. Maximum LiftMed.	Med.	0	—
65. After LiftoffEasy	Easy	4	80.0%
66. Slipping ShellMed.	Med.	0	—
67. Calibrating by PeriodMed.	Med.	1	33.3%
68. Cascading DisadvantageMed.	Med.	0	—
69. Layered WindMed.	Med.	1	50.0%
70. Equal-Time Dead ZoneMed.	Med.	0	—
71. Hidden GaussianEasy	Easy	2	100.0%
72. Tilted Free FallMed.	Med.	1	—
73. Coalescence CeilingMed.	Med.	1	—
74. Free Ballistic CaptureMed.	Med.	0	—
76. Lifting a Submerged ConeMed.	Med.	0	—
77. The Yielding WedgeMed.	Med.	1	50.0%
78. Decay InvariantsMed.	Med.	1	—
79. Pumping the SwingHard	Hard	2	66.7%
80. Compound AccelerationMed.	Med.	1	—
81. Triangular JointsMed.	Med.	0	0.0%
82. Hexagonal PivotMed.	Med.	1	—
83. Lunar-Gravity ParabolaEasy	Easy	1	—
84. Rigid Rod Conical PendulumMed.	Med.	0	—
85. Successive ReboundMed.	Med.	0	—
86. Reluctant AnvilHard	Hard	2	33.3%
87. Subterranean PerihelionMed.	Med.	0	—
88. Apsides After ImpulseMed.	Med.	1	—
89. Torsion Disk ReboundMed.	Med.	2	40.0%
90. Threshold of MotionEasy	Easy	0	—
91. Whirling Bowstring StabilityMed.	Med.	2	100.0%
92. Inverted CascadeMed.	Med.	0	—
93. Floater's TollMed.	Med.	0	—
94. Pendulum Sweet SpotMed.	Med.	0	—
95. Background-Limited CountingMed.	Med.	0	—
96. Capped RangeMed.	Med.	1	—
97. Climbing in PlaceMed.	Med.	0	—
98. Crosswise Frictional HeatingMed.	Med.	0	—
99. Trapped Rotational EnergyEasy	Easy	1	—
100. Asymptotic CruiseMed.	Med.	1	50.0%
101. Pseudogravity DecayEasy	Easy	0	0.0%
102. Convection on a ScaleMed.	Med.	0	—
103. Asymptotic StoppingMed.	Med.	1	—
104. Coriolis CancellationHard	Hard	1	—
105. Diving Board FailureMed.	Med.	0	—
106. Keplerian Catch-UpMed.	Med.	0	—
107. Comparing Mint BatchesEasy	Easy	0	—
108. Common Rim SpeedEasy	Easy	0	—
109. Decoupled DescentEasy	Easy	1	50.0%
110. Traction-Limited LapMed.	Med.	1	—
111. Galilean Energy AccountingMed.	Med.	0	—
112. Power-Limited MicroswimmerEasy	Easy	2	50.0%
113. Synodic TerminatorMed.	Med.	1	—
114. Climbing the WellMed.	Med.	2	100.0%
115. Orbital ShrapnelHard	Hard	1	—
116. Crossed Spring EquilibriumMed.	Med.	0	—
117. Rolling Oscillator on a Slippable PlatformMed.	Med.	0	—
118. Fountain Apparent WeightMed.	Med.	2	100.0%
119. Closing the LoopHard	Hard	3	100.0%
120. Spinning ManifoldMed.	Med.	2	66.7%
121. Where the Heat GoesMed.	Med.	1	25.0%
122. Heavy-Planet DrillMed.	Med.	0	—
123. Linear Drag StopEasy	Easy	2	100.0%
124. Centrifugal FailureMed.	Med.	1	—
125. After the ReleaseEasy	Easy	3	60.0%
126. Fluctuation-Induced BoostHard	Hard	0	—