1.5 Dynamics of a Solid Body

Irodov Problems 1.234 to 1.289.

56problems
143figures
Difficulty3.0avgDifficulty: 0 rated 1, 14 rated 2, 29 rated 3, 12 rated 4, 1 rated 5; mean 3.0.
Uniqueness3.3avgUniqueness: 1 rated 1, 8 rated 2, 24 rated 3, 20 rated 4, 3 rated 5; mean 3.3.

No.	Title	Difficulty	Uniqueness	Methods
1.234	No Rotation Locates the Mass Center	Difficulty 3 of 5	Uniqueness 3 of 5	newton second law · torque · center of mass
1.235	Cross Product First, Arm for Free	Difficulty 2 of 5	Uniqueness 2 of 5	torque · vector decomposition
1.236	Slide Both Forces to Their Crossing	Difficulty 2 of 5	Uniqueness 3 of 5	torque · vector decomposition
1.237	Three Forces Collapse to One Line	Difficulty 3 of 5	Uniqueness 3 of 5	torque · vector decomposition
1.238	Where the One Third Comes From	Difficulty 2 of 5	Uniqueness 1 of 5	moment of inertia · rigid body rotation
1.239	Rings and Slabs Build the Inertia	Difficulty 2 of 5	Uniqueness 2 of 5	moment of inertia · symmetry
1.240	Two Flat Axes Make the Third	Difficulty 2 of 5	Uniqueness 4 of 5	moment of inertia · symmetry
1.241	A Hole Is Negative Mass	Difficulty 3 of 5	Uniqueness 4 of 5	moment of inertia · center of mass
1.242	The Shell a Sphere Grows	Difficulty 2 of 5	Uniqueness 3 of 5	moment of inertia · symmetry
1.243	Half the Cylinder Joins the Load	Difficulty 2 of 5	Uniqueness 2 of 5	torque · moment of inertia · newton second law
1.244	The Bar That Chases the Thread	Difficulty 3 of 5	Uniqueness 4 of 5	newton second law · torque · constraints pulleys · rigid body rotation
1.245	Work Beats a Varying Torque	Difficulty 2 of 5	Uniqueness 3 of 5	work energy · torque · moment of inertia · rigid body rotation
1.246	Why the Two Tensions Cannot Match	Difficulty 3 of 5	Uniqueness 3 of 5	torque · newton second law · constraints pulleys · rigid body rotation
1.247	Half the Pulley Rides Along	Difficulty 3 of 5	Uniqueness 2 of 5	newton second law · torque · work energy · friction
1.248	Two Contacts Brake One Cylinder	Difficulty 4 of 5	Uniqueness 4 of 5	friction · torque · rigid body rotation · free body
1.249	Friction Spread over a Whole Face	Difficulty 3 of 5	Uniqueness 3 of 5	friction · torque · moment of inertia · rigid body rotation
1.250	The Braking Law Sets the Average	Difficulty 3 of 5	Uniqueness 4 of 5	rigid body rotation · differential equation · torque
1.251	Wound or Hanging, the Inertia Holds	Difficulty 4 of 5	Uniqueness 4 of 5	moment of inertia · torque · newton second law
1.252	Rolling Sets Its Own Friction	Difficulty 2 of 5	Uniqueness 2 of 5	rolling · newton second law · friction · moment of inertia
1.253	When Unwinding Sets the Fall	Difficulty 2 of 5	Uniqueness 2 of 5	newton second law · moment of inertia · rigid body rotation · work energy
1.254	The Car Only Changes Effective Gravity	Difficulty 3 of 5	Uniqueness 3 of 5	newton second law · torque · frames of reference
1.255	The Rim Never Enters the Answer	Difficulty 3 of 5	Uniqueness 4 of 5	newton second law · torque · constraints pulleys
1.256	Pulling Down Raises the Friction Ceiling	Difficulty 3 of 5	Uniqueness 3 of 5	rolling · torque · friction · newton second law
1.257	Which Way a Pulled Spool Rolls	Difficulty 3 of 5	Uniqueness 4 of 5	rolling · torque · work energy
1.258	Two Spins Add to One Fall	Difficulty 3 of 5	Uniqueness 4 of 5	torque · rigid body rotation · constraints pulleys
1.259	Everything Measured from the Motionless Point	Difficulty 4 of 5	Uniqueness 4 of 5	torque · rigid body rotation · constraints pulleys
1.260	The Thread End Outruns Both Bodies	Difficulty 3 of 5	Uniqueness 3 of 5	newton second law · rigid body rotation · work energy
1.261	The Ball Keeps Two Sevenths	Difficulty 3 of 5	Uniqueness 3 of 5	rolling · torque · newton second law · free body
1.262	Friction Trades Spin for Speed	Difficulty 3 of 5	Uniqueness 3 of 5	friction · rolling · torque · work energy
1.263	Rolling Delays the Ball's Departure	Difficulty 3 of 5	Uniqueness 3 of 5	rolling · energy conservation · circular motion
1.264	The Speed That Clears the Edge	Difficulty 4 of 5	Uniqueness 4 of 5	energy conservation · rolling · moment of inertia · circular motion
1.265	When A Rides over the Top	Difficulty 4 of 5	Uniqueness 5 of 5	rolling · energy conservation · center of mass · circular motion
1.266	Twice the Energy You Expect	Difficulty 3 of 5	Uniqueness 4 of 5	frames of reference · center of mass · rolling
1.267	A Sphere Walked Around a Circle	Difficulty 4 of 5	Uniqueness 5 of 5	rolling · rigid body rotation · moment of inertia · center of mass
1.268	Inertial Forces Add at the Center	Difficulty 2 of 5	Uniqueness 3 of 5	non inertial frame · center of mass · vector decomposition
1.269	A Tilted Rotor Twists Its Bearings	Difficulty 3 of 5	Uniqueness 3 of 5	non inertial frame · torque · rigid body rotation
1.270	The Rod's Cone Needs More Spin	Difficulty 3 of 5	Uniqueness 3 of 5	non inertial frame · torque · circular motion
1.271	Where the Floor Really Pushes Back	Difficulty 4 of 5	Uniqueness 4 of 5	angular momentum · friction · torque
1.272	The Sleeve Steals the Rod's Spin	Difficulty 3 of 5	Uniqueness 3 of 5	angular momentum · energy conservation · moment of inertia
1.273	What the Halves Owe Each Other	Difficulty 4 of 5	Uniqueness 4 of 5	angular impulse · impulse · rigid body rotation · center of mass
1.274	The Plate That Weighs Four Thirds	Difficulty 4 of 5	Uniqueness 4 of 5	collisions · angular momentum · moment of inertia · energy conservation
1.275	Where to Hit and Feel Nothing	Difficulty 4 of 5	Uniqueness 4 of 5	angular momentum · angular impulse · energy conservation
1.276	Pulling Inward Always Costs Energy	Difficulty 3 of 5	Uniqueness 2 of 5	angular momentum · moment of inertia · work energy
1.277	The Disc Turns Back Beneath Him	Difficulty 3 of 5	Uniqueness 3 of 5	angular momentum · relative motion · torque
1.278	Sticking Together Always Burns Energy	Difficulty 2 of 5	Uniqueness 2 of 5	angular momentum · collisions · moment of inertia
1.279	Why Four Is the Magic Ratio	Difficulty 4 of 5	Uniqueness 4 of 5	collisions · momentum conservation · angular momentum · energy conservation
1.280	Turning the Spin Turns the Platform	Difficulty 5 of 5	Uniqueness 5 of 5	angular momentum · rigid body rotation · moment of inertia · torque
1.281	The Speed That Frees One Bearing	Difficulty 3 of 5	Uniqueness 3 of 5	torque · rigid body rotation · circular motion · newton second law
1.282	Angular Momentum Refuses the Rotation Axis	Difficulty 4 of 5	Uniqueness 4 of 5	angular momentum · rigid body rotation · moment of inertia · torque
1.283	Tilt Cancels Out of Precession	Difficulty 3 of 5	Uniqueness 3 of 5	angular momentum · torque · rigid body rotation · circular motion
1.284	The Elevator Sets the Effective Gravity	Difficulty 3 of 5	Uniqueness 3 of 5	torque · angular momentum · non inertial frame · moment of inertia
1.285	Precession Follows the Effective Vertical	Difficulty 3 of 5	Uniqueness 4 of 5	angular momentum · torque · non inertial frame · frames of reference
1.286	Turning the Spin Axis Loads Bearings	Difficulty 2 of 5	Uniqueness 3 of 5	torque · angular momentum · moment of inertia · rigid body rotation
1.287	The Bearings Feel the Wobble	Difficulty 3 of 5	Uniqueness 3 of 5	angular momentum · torque · rigid body rotation
1.288	A Turning Ship Pitches Its Flywheel	Difficulty 2 of 5	Uniqueness 3 of 5	angular momentum · torque · rigid body rotation
1.289	A Turn Loads the Outer Rail	Difficulty 3 of 5	Uniqueness 4 of 5	torque · angular momentum · circular motion · rigid body rotation