Stephanie performs 400 Joules of work when she pushes Brianna 2 meters across the room with a force of 200 Newtons, as work done is the product of force and distance.
To calculate the work Stephanie performs when she pushes Brianna across the room, it is important to understand the concept of work in physics. Work is defined as the transfer of energy when a force is applied over a distance and in the direction of the force. Specifically, work done is the product of the force applied and the distance over which it is applied, given by the formula W = F × d, where W represents work, F represents force, and d represents distance.
In Stephanie's case, the work done can be calculated as follows:
Work (W) = Force (F) × Distance (d)
Work = 200 Newtons × 2 meters
Work = 400 Joules
Therefore, Stephanie performs 400 Joules of work when she pushes Brianna 2 meters across the room.