Answer:
Friction force is 0.1375 N
Solution:
As per the question:
Radius of the metal disc, R = 4.0 cm = 0.04 m
Magnetic field, B = 1.25 T
Current, I = 5.5 A
Force on a current carrying conductor in a magnetic field is given by considering it on a differential element:

Integrating the above eqn:

(1)
Now the torque is given by:
(2)
From eqn (1) and (2):

Thus the Frictional force is given by:

The electric field at point A located 2.00 mm above the dipole's midpoint is 5.287 X 10¹³ N/C.
<h3>
Electric field of the positive particle</h3>
The electric field is calculated as follows;
E = kq/r²
where;
- r is the distance between the charges
- k is Coulomb's constant
- q is magnitude of the charge
midpoint of 3.08 m, x = 1.54 mm
r(1.54 mm, 2.00 mm)
|r| = √(1.54² + 2²)
|r| = 2.52 mm
E = (9 x 10⁹ x 37.3 x 10⁻³)/(2.52 x 10⁻³)²
E = 5.287 X 10¹³ N/C
Thus, the electric field at point A located 2.00 mm above the dipole's midpoint is 5.287 X 10¹³ N/C.
Learn more about electric field here: brainly.com/question/14372859
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I think it's D. Usually, to find the volume of an irregularly shaped object, you put it in water with a labeled beaker to measure how much the water rises. The balance would be used to measure the mass in grams.