Please help is momentum in the x-direction, m Vx, conserved? is momentum in the y-direction m Vy, considered? to help understand your answer, describe the external force and which direction (x or y) it acts along.

grav potential energy

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.

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.