To move a 15-kilogram object 3 meters off the ground, 441 joules of work are required. Work, as defined by the Franciscan University of Steubenville, is the product of the force needed to move an object and the distance moved.
The object has a mass of 15 kilograms. Therefore, it weighs 147 newtons on Earth, where gravitational acceleration is 9.8 meters per second per second. To counteract gravity, the acting force needs to be at least 147 newtons, It has to move 3 meters upward. When multiplying force by distance, the product comes to 441 joules, where joules are the standard unit of work.