In which of the following graphs is the runner running the fastest?

The answer is B.

Explanation:

I know you don't need this anymore, but for those who ask the same question, it's B since the graph is increasing at a faster past than A. I would insert an image to this, but it won't let me.

answer; i believe the correct answer is (40,000 j) good luck

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.