1.4 Universal Gravitation

Irodov Problems 1.200 to 1.233.

34problems
48figures
Difficulty2.9avgDifficulty: 0 rated 1, 11 rated 2, 14 rated 3, 9 rated 4, 0 rated 5; mean 2.9.
Uniqueness3.0avgUniqueness: 1 rated 1, 10 rated 2, 11 rated 3, 12 rated 4, 0 rated 5; mean 3.0.

No.	Title	Difficulty	Uniqueness	Methods
1.200	Circular Speed Alone Fixes the Period	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · newton second law · circular motion · dimensional analysis
1.201	Kepler's Third Law Places Jupiter	Difficulty 3 of 5	Uniqueness 3 of 5	gravitation · orbits kepler · circular motion · newton second law
1.202	The Ellipse's Hidden Equivalent Circle	Difficulty 3 of 5	Uniqueness 4 of 5	gravitation · orbits kepler · circular motion · limiting cases
1.203	Radial Fall as Degenerate Ellipse	Difficulty 3 of 5	Uniqueness 4 of 5	orbits kepler · limiting cases · gravitation
1.204	Scaling the Solar System Keeps Time	Difficulty 2 of 5	Uniqueness 3 of 5	orbits kepler · gravitation · dimensional analysis
1.205	Only the Total Mass Matters	Difficulty 3 of 5	Uniqueness 3 of 5	gravitation · orbits kepler · center of mass · newton second law
1.206	A Point Mass Against a Rod	Difficulty 3 of 5	Uniqueness 2 of 5	gravitational potential · gravitation · limiting cases
1.207	Angular Momentum from the Two Apsides	Difficulty 3 of 5	Uniqueness 2 of 5	orbits kepler · angular momentum · energy conservation · gravitation
1.208	Only the Semi-Major Axis Survives	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · orbits kepler · energy conservation · angular momentum
1.209	One Point Fixes the Whole Ellipse	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · orbits kepler · energy conservation · angular momentum
1.210	Aiming Parameter Fixes the Closest Approach	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · energy conservation · angular momentum · orbits kepler
1.211	Every Shell Attracts as Concentrated	Difficulty 3 of 5	Uniqueness 3 of 5	gravitation · gravitational potential · potential energy · symmetry
1.212	Opposite Shell Patches Cancel Inside	Difficulty 3 of 5	Uniqueness 4 of 5	gravitation · symmetry · limiting cases
1.213	Doubling a Hemisphere into a Sphere	Difficulty 4 of 5	Uniqueness 4 of 5	gravitational potential · symmetry · gravitation
1.214	Shell Theorem Inside and Outside	Difficulty 3 of 5	Uniqueness 2 of 5	gravitation · gravitational potential · symmetry · limiting cases
1.215	A Cavity's Field from Two Spheres	Difficulty 3 of 5	Uniqueness 3 of 5	gravitational potential · symmetry · gravitation
1.216	A Sphere Crushed by Its Gravity	Difficulty 3 of 5	Uniqueness 3 of 5	gravitation · differential equation · dimensional analysis
1.217	Assembling a Sphere Against Gravity	Difficulty 3 of 5	Uniqueness 3 of 5	gravitational potential · potential energy · gravitation
1.218	The Synodic Rhythm of Close Orbits	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · orbits kepler · approximation expansion · circular motion
1.219	Gravity, Spin, and the Sun Compared	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · non inertial frame · dimensional analysis
1.220	How High Before Gravity Drops	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · approximation expansion · limiting cases
1.221	Approaching Escape Speed from the Pole	Difficulty 2 of 5	Uniqueness 3 of 5	gravitation · differential equation · energy conservation · limiting cases
1.222	How Orbital Speed Sets the Altitude	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · newton second law · orbits kepler · limiting cases
1.223	The Satellite That Never Moves	Difficulty 3 of 5	Uniqueness 3 of 5	gravitation · orbits kepler · newton second law · frames of reference
1.224	When the Satellite Outpaces the Ground	Difficulty 4 of 5	Uniqueness 3 of 5	gravitation · orbits kepler · relative motion · circular motion
1.225	Retrograde Orbit Against a Spinning Earth	Difficulty 3 of 5	Uniqueness 4 of 5	gravitation · non inertial frame · circular motion · frames of reference
1.226	Earth's Spin Splits Satellite Kinetic Energy	Difficulty 2 of 5	Uniqueness 3 of 5	gravitation · orbits kepler · relative motion · frames of reference
1.227	Drag Spirals a Moon Satellite Down	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · orbits kepler · differential equation · energy conservation
1.228	Escaping a Smaller World	Difficulty 2 of 5	Uniqueness 1 of 5	gravitation · energy conservation · newton second law
1.229	Braking a Grazing Parabola into a Circle	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · orbits kepler · energy conservation
1.230	From Circular Orbit to Escape Speed	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · newton second law · energy conservation
1.231	Where Earth and Moon Pulls Cancel	Difficulty 2 of 5	Uniqueness 2 of 5	gravitation · dimensional analysis · limiting cases
1.232	Escaping One Well, Landing in Another	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · gravitational potential · energy conservation · approximation expansion
1.233	Add Along Earth's Motion to Escape	Difficulty 4 of 5	Uniqueness 4 of 5	gravitation · energy conservation · vector decomposition · optimization