For slowly moving objects, the drag force in water is approximately proportional to the speed of the object. The Escherichia coli (E. coli) bacterium propels itself slowly through water by means of long, thin structures called flagella. If the force exerted on the water by the flagella doubles,
the velocity of the bacterium

doubles.

does not change.

increases by a factor of four.

decreases by a factor of four.

decreases by half.

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.