A bungee jumper falls off a tower and travels 4 seconds before the bungee cord starts to slow her down. What was her average velocity in free fall?

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up

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.