Gravity Problems
Some SAT Physics exam questions require knowledge of gravity, laws of gravitation, orbits and Kepler's Laws.
1. Two satellites orbit the earth at radii r1 and r2 with speeds v1 and v2. Which of the following equalities is true:a) v12/v22 = r1/r2
b) v12/v22 = r2/r1
c) v1/v2 = r2/r1
d) v2/v1 = r2/r1
2. A particle of mass m moves at a speed v along a circular path of radius r. If ω is the angular velocity, f is the frequency and T is the period, all of the following expressions represent the magnitude of the centripetal force applied to the particle except:
a) m·v2/r
b) 4·π2·f2m·r
c) 4·π2·m·r/T2
d) m·v/r2
e) m·r·ω2