Okay, let's think this through step-by-step:
* The rate of energy transfer is 50 J/s
* We need to calculate the energy transferred in 4 seconds
* So we would calculate:
Energy in 4 seconds = Rate x Time
= 50 J/s x 4 s
= 200 J
So the heat energy produced within 4 seconds with an energy transfer rate of 50 J/s is 200 J.
Let me know if you have any other questions!