5 A truck travelling at 25 m/s puts on its brakes for 4 s. This produces an acceleration of –2 m/s. What is the truck's velocity after braking?

The truck's velocity after braking = 17m/s.

Explanation:

Given: Initial velocity(i) = 25 m/s

Time(t)  = 4s

Acceleration(a) = -2 m/s ²

We use the following formula to compute final velocity (v):

Hence, the truck's velocity after braking = 17m/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.