A stationary 1000 kg cannon fired a 100 kg cannonball at a speed of 30m/s to the right. The recoil speed(the speed it bounces to the left) of the cannon in units of m/s is most nearly

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.