The best option is C. This is due to friction.
Answer:
the speed of the ball is 10 m/s
Explanation:
Given;
magnitude of exerted force, F = 400 N
mass of the ball, m = 2 kg
radius of the circle, r = 0.5
The speed of the ball is calculated by applying centripetal force formula;

Therefore, the speed of the ball is 10 m/s
micrometer is used to measure the diameter of a thin wire
Answer:
-32.5 * 10^-5 J
Explanation:
The potential energy of this system of charges is;
Ue = kq1q2/r
Where;
k is the Coulumb's constant
q1 and q2 are the magnitudes of the charges
r is the distance of separation between the charges
Substituting values;
Ue = 9.0×10^9 N⋅m2/C2 * 5.5 x 10^-8 C *( -2.3 x10^-8) C/(3.5 * 10^-2)
Ue= -32.5 * 10^-5 J
It is either 98 J or 98 N let me check..