An aerobatic airplane pilot experiences weightlessness as she passes over the top of a loop-the-loop maneuver. the acceleration of gravity is 9.8 m/s 2 . if her speed is 430 m/s at this time, find the radius of the loop. answer in units of km.

The acceleration due to gravity serves as the centripetal acceleration of the objects that orbits the Earth. The centripetal acceleration due to gravity is calculated through the equation,

    a = v²/r

where v is the speed and r is the radius. Substituting the known values to the equation,

   9.8 m/s² = (420 m/s)² / r

The value of r from the equation is 18000 m or equal to 18 km.

18 km