Astudent pushes a 50 kg box of books on a flat surface with a force of 120 n at an angle of 60° on the horizontal. if the surface is friction free, how far does the box move in 5 seconds assuming it started moving from rest? a. 6.0 m
b. 8.5 m
c. 15 m
d. 4.6 m

c. 15 m

Explanation:

We apply Newton's second law in the x direction:

∑Fₓ = m*a

120*cos(60°) = 50*a

Block kinematics

The block moves with uniformly accelerated movement, so we apply the following formula to calculate the distance

d = 15m

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.