<span> answer>>>>electric force <<<<by the way i don't like physics but i answer this for you ^-^</span>
<span>This is because centripetal force is just the net force of a circular motion. There are no attractive or repulsive forces here. This is not the case here. </span>
<span>The gravitational force is a force reliant on mass and attraction of the masses. There are attractive forces here, but not really repulsive forces. </span>
<span>The electric force is the only one that would make sense because it has to do with a relationship between charges and includes both repulsive and attractive forces.</span>
1) 3 miles/Hour
The speed is defined as the distance covered divided by the time taken:

where
d = 1.5 mi is the distance
t = 0.5 h is the time taken
Substituting,

2) 1.34 m/s south
Velocity, instead, is a vector, so it has both a magnitude and a direction. We have:
is the displacement in meters
is the time taken in seconds
Substituting,

And the direction of the velocity is the same as the displacement, so it is south.
Higher voltage means faster rotation. Changing the voltage polarity changes the direction of the motor.