Past exam of the physics B course of the University of Cambridge 2010 Paper 1 Section A 2 Solution 2026-10-20
Use local east, north and up axes. At latitude , and eastward velocity is . The Coriolis acceleration isIts horizontal part is southward, so the lift must acquire a northward component: bank left, with the north wing lower. For the requested local Coriolis correction, let the vertical lift balance . The Coriolis bank angle for eastward flight isUse and . Including the upward Coriolis term replaces by and changes the answer by only about . This is the horizontal Coriolis compensation, not a full calculation of a curved constant-latitude flight path. The rotation rate follows Earth's sidereal period.[ref]
Earth Fact Sheet by National Aeronautics and Space Administration. Orbital parameters: sidereal rotation period 23.9345 hours
Past exam of the physics B course of the University of Cambridge 2011 Paper 1 Section A A5 Solution 2026-10-20
Use a local horizontal plane, constant gravity and first order in Earth's angular speed. Let point along the initial horizontal shot, to the gunner's left and upward. At the North pole, . Maximum unperturbed range at equal launch and landing heights requires a elevation, givingThe leading Coriolis acceleration is , while vertical motion has no first-order Coriolis correction. With zero initial lateral displacement and velocity,Here , and . The miss is to the right of the aiming direction, independent of its azimuth at the pole. The flight time is about , so . This polar projectile Coriolis deflection uses the usual flat, uniform-gravity approximation; planetary curvature and variation of gravity are beyond its accuracy. Using the polar gravity rather than changes the estimate by less than one percent. Earth's sidereal rotation period, rather than the solar day, sets .[ref]
Earth Fact Sheet by National Aeronautics and Space Administration. Orbital parameters: sidereal rotation period 23.9345 hours; bulk parameters: polar surface acceleration
Polar projectile deflection
. Details. Past exam of the physics B course of the University of Cambridge 2013 Paper 2 Section A A2 Solution 2026-10-20
In the ideal semidiurnal tide model, successive high tides occur after the Earth–Moon relative angle advances by . Since the motions have the same sense, subtract their angular speeds:The lunar orbital period is sidereal, so the consistent terrestrial rotation period is . With , this gives about 12 h 25 min. The sidereal terrestrial period is distinct from the 24-hour solar day.[ref]
Earth Fact Sheet by National Aeronautics and Space Administration. Orbital parameters, sidereal rotation period 23.9345 h and length of day 24 h
If the Earth's rotation is approximated as one revolution in 24 hours, the same calculation instead gives 12 h 27 min. That small difference is the day convention, not a change of sign in the relative angular speed. Actual coastal tide times also depend on ocean dynamics and the solar tide.
For this molecular escape-speed temperature estimate, . Equating this to the surface escape-speed square givesThis evaluation keeps the paper's and , and uses externally documented , and .[ref]
Earth Fact Sheet by National Aeronautics and Space Administration. Bulk parameters: gravitational parameter GM
[ref]CODATA recommended values of the fundamental physical constants 2014 by National Institute of Standards and Technology. Atomic mass constant and Boltzmann constant
The corresponding escape speed is about .This is the requested speed-scale comparison. Atmospheric escape can occur from the high-speed tail at lower temperature; molecular dissociation and ionization also prevent treating an actual gas at this temperature as unchanged neutral nitrogen molecules.
