1. A car starts from rest and accelerates at a constant rate of 2.5 m/s2. What is the car's velocity after the car has traveled 100 m?

Explanation:

u (initial velocity) = 0

acceleration = 2.5 m/s²

s (distance) = 100 m

Then,

v² = u² + 2as

v² = (0)² + 2×2.5×100

v² = 0 + 500

v² = 500

v = √500

v = 10√5 m/s

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.