Final answer:
The work done by a person who applies a force of 45 N to move an object over a distance of 20 m is 900 Joules.
Step-by-step explanation:
The student has asked about the work done when a force is applied to move an object over a certain distance. Work is a physical concept in Physics and is calculated as the product of the force applied in the direction of the movement and the distance over which the force is applied. In this case, the person has applied a force of 45 N to move the object over a distance of 20 m.
To calculate the work done, we use the formula Work (W) = Force (F) × Distance (d). Here, the force is 45 N and the distance is 20 m, so the work done is:
W = F × d
W = 45 N × 20 m
W = 900 Joules (J)
Therefore, the person has done 900 Joules of work in moving the object.