Answer:
Kinematics is the study of motion of a system of bodies without directly considering the forces or potential fields affecting the motion.
Answer: two electrons
Explanation: The first principal energy level contains only an s sublevel; therefore, it can hold a maximum of two electrons. Each principal energy level above the first contains one s orbital and three p orbitals. A set of three p orbitals, called the p sublevel, can hold a maximum of six electrons.
Answer:
The constant force is 263.55 newtons
Explanation:
There's a rotational version of the Newton's second law that relates the net torque on an object with its angular acceleration by the equation:
(1)
with τ the net torque and α the angular acceleration. It’s interesting to note the similarity of that equation with the well-known equation F=ma. I that is the moment of inertia is like m in the linear case. The magnitude of a torque is defined as

with F the force applied in some point, r the distance of the point respect the axis rotation and θ the angle between the force and the radial vector that points toward the point the force is applied, in our case θ=90 and sinθ=1, then (1):
(2)
Because the applied force is constant the angular acceleration is constant too, and for constant angular acceleration we have that it's equal to the change of angular velocity over a period of time:

It's important to work in radian units so knowing that 
(3)
The moment of inertia of a disk is:
(4)
with M the mass of the disk and R its radius, then

using the values (3) and (4) on (2)
(2)
Because the force is applied about the rim of the disk r=R=1.50:

I'm pretty sure that you're talking about an "electromagnet",
and that you actually meant an iron core .