A heavy transport drone on an exoplanet has a mass of 240 kg. When ascending vertically with an upward acceleration of 1.5 m/s2, the total upward thrust force exerted by its rotors is 3240 N.
What is the gravitational field strength, ggg, of this exoplanet?
9.0 N/kg9.0\text{ N/kg}9.0 N/kg
12.0 N/kg12.0\text{ N/kg}12.0 N/kg
13.5 N/kg13.5\text{ N/kg}13.5 N/kg
15.0 N/kg15.0\text{ N/kg}15.0 N/kg