a 2.61 kg block is at the top of a 10.2 m long incline, tilted at 15.0°, with uk = 0.220. what is the block's final velocity when it reaches the bottom of the incline?

not too sure thinking all accelerations are pointed down

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.