Which is a result of using a machine?
The mechanical advantage makes the work output greater than the work input.
The machine can put out force without having any force applied to it.
Alarge force can be exerted through a long distance to have a small force exerted through a short distance.
Alarge force can be exerted through a short distance to have a small force exerted through a long distance.

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.