Explanation

Work is the amount of energy transferred when a force acts on an object, causing it to move. The formula for work done is: work = force x distance x cos(theta) where force is the force applied on the object, distance is the distance moved by the object, and theta is the angle between the force and the direction of motion. In the given problem, a stone of mass m kg is held h meters above the floor for 50s. We need to find the work done in joules over this period. Since the stone is being held stationary, its distance moved is zero. Therefore, the work done on the stone is also zero. Hence, the answer is O, which means zero. The option that represents zero is O.

Work is the amount of energy transferred when a force acts on an object, causing it to move. The formula for work done is: work = force x distance x cos(theta) where force is the force applied on the object, distance is the distance moved by the object, and theta is the angle between the force and the direction of motion. In the given problem, a stone of mass m kg is held h meters above the floor for 50s. We need to find the work done in joules over this period. Since the stone is being held stationary, its distance moved is zero. Therefore, the work done on the stone is also zero. Hence, the answer is O, which means zero. The option that represents zero is O.